I'm dealing with this same issue. Finally got my 5 axis all wired up and working. I'm currently using COR and machine zero for work offsets. For cam, I'm using HSMworks. Fortunately there is a customizable post for this. I'm not a programmer, and it's a bit of a pain to rewrite the post, but doable. Tool offsets and work offsets are a PITA. If I understand correctly, without tcpc you must have all your tools in the cam package and re-post if you change an end mill dull/broken etc because the tool offsets change the toolpath. The compensation must be done in the post or the CAM package. You can't just change the tool table in Mach. If anybody is doing this already and has any suggestions, I'm all ears.
As it is, looks like I'm going to be confining 5 axis simultaneous to rough contouring work. Everything else will need to be done in 3 or 3+2. Otherwise, I have to be going back and re-writing tool paths whenever a new tool is installed.