Business libraries are used to create the reusable architecture artifacts - actors, roles, processes, services etc. The Business Architecture package then contains all of the business viewpoint diagrams e.g. organisation view and business process coordination views.

Guidelines can be communicated in a few different ways. I usually create guideline diagrams that show the agreed elements and relationships to be used for each type of diagram, and suggest best diagram layout. I usually place these guidelines inside EA but in a separate root node from the model content.

We send a printed copy of the training booklet to you - it contains all the slides and comprehensive notes which are great for revision after your course. We can send the exercises in PDF format if you don't receive your training booklet before your course. We also have summary notation sheets in PDF format that you can download from the Resources page on our website. A link to our online resources:
http://www.hippo-software.co.uk/pages/Resources.htm
You can see our full public EA training schedule on our website:
http://www.hippo-software.co.uk/pages/EAPublicWebinars.htm

This presentation was created as a standalone entity to give a little taster of the possibilities available when using ArchiMate in Enterprise Architect. The aspects spoken about today are covered in our training, but this wasn't just one module. You ask about module 87 - this is the training module in our catalogue that covers the commonly used features of the ArchiMate Business Layer and it includes more than the things in the presentation. Some other aspects shown today are covered in other training modules. For example, the automatic colour coding in this presentation is covered in the Strategy module (module 90), when we create a Capability map.
Have a look through this page for all the things we cover in our various training online and face-to-face courses:
http://www.hippo-software.co.uk/pages/ArchiMate.htm
The presentation today was based on a subset of our EA and ArchiMate Business Essentials. By the way we have a 1-day public course running which covers this module in full, plus ArchiMate Motivation and ArchiMate Strategy. It's called EA and ArchiMate Business. Course outline in the Files tab above, or look on our website:
http://www.hippo-software.co.uk/pages/EAPublicWebinars.htm

When the access relationship is shown pointing towards a business object element it means the business object is being changed in some way. If the access relationship points away from the business object, that means it is simply being read (or accessed). There was (still is perhaps?) an issue when using the quick linker to connect business objects to other ArchiMate elements as the line can only be created in one direction.

Every connector in EA has a source element and a target element, determined by the direction you create the line. If you need to flip a relationship round, it is normally best to right-click and choose 'Advanced->Reverse Direction', rather than just changing the 'source->destination' direction. Visually, you see the same thing on the diagram, but using 'Reverse Direction' swaps the source and target elements for the relationship, as if you had actually drawn the line the other way in the first place. Just changing the direction in the properties window simply moves the arrowhead to the source end of the line so the relationship matrix and other functions in Enterprise Architect would show the 'wrong' information. I think strictly speaking the ArchiMate standard says that an access relationship should always be created from a business process to the business objects. Therefore, to comply with the standard, it might be best to create them all in that direction and then use the direction attribute to visually change the arrowhead to point the appropriate way (source to destination or destination to source). I suspect this is why the quick linker only supports creating an access relationship in one direction.
The official definition says - "the direction of the [access] relationship is always from an active structure element or a behavior element to a passive structure element, although the notation may point in the other direction to denote “read” access, and in both directions to denote read-write access".
However, if you want to create a relationship matrix in EA to demonstrate which business processes update which business objects and another matrix to demonstrate which processes read which objects, you would need the lines to point in the right direction, not just have the arrow at the 'wrong' end. I guess it depends on what information you need to get out of your model later and in what format?!
https://pubs.opengroup.org/architecture/archimate3-doc/chap05.html#_Toc10045319

I guess the Business Process does access the Business Object - either to read the data or to edit the data

Yes ArchiMate is an industry standard maintained by The Open Group (and closely aligned to TOGAF - The Open Groups Architecture Framework). There are other architecture frameworks supported by EA such as Zachman, DoDAF and MODAF. ArchiMate is becoming ever more popular in the UK and Europe. The notation is relative simple and intuitive and it mixes well with other standards for detailed design such as UML/SysML and BPMN.

You could write a script to add up the average time of sub-processes and apply to the parent process. Aggregation is a shared relationship - allowing the subprocesses to potentially be reused by another level 0 process. Composition indicates a stricter binding where the subprocess would be tied to just one level 0 process. We often use just aggregation in the business layer to keep things flexible

I was using tagged values to hold custom properties on the ArchiMate artifacts. This is entirely optional if you have extra information you wish to collect. I would add to that and say that the Serving relationship is used to connect a service to the thing that it serves, whereas tagged values are there to records additional properties specific to a particular object or object type.

ArchiMate is a large toolkit of element types and suggested viewpoints (diagrams). For internal business behaviour, you would typically use a Business Function element. you could also use a business service to show how one part of an organisation interacts with another distinct part of the same organisation. Especially if there is a formal interface between the different parts of the organisation.

Business libraries are used to create the reusable architecture artifacts - actors, roles, processes, services etc. The Business Architecture package then contains all of the business viewpoint diagrams e.g. organisation view and business process coordination views.