Custom toolbar

To make a modal toolbar/dialog one can subscribe this to the events provided i.e. OnEditDocument.

However, is it possible within the IFM "framework" to make a non-modal custom toolbar interacting with FEFLOW?

At least theoretically you can bring up a non-modal dialog via IFM. The practical implementation, however, might be somewhat complex as you would have to consider the event handling and message routing, and you might need some knowledge how FEFLOW does this internally. So I'd recommend this only with a lot of programming experience, and you might need the help of our programmers. For a toolbar there is another limitation: You can interact with FEFLOW only when FEFLOW has called one of the call-backs. From a non-modal toolbar, you might rather want interaction with FEFLOW at any given time which is currently not possible.