The complex profile tool works quite nice for log walls. I'm assisting with aa big log home right now. We've also been in contact with a firm out of Montana or Oregon that has been doing exclusively log structures in archicad for years.
To get the end cuts looking right, look into Solid Element Operations. We've used complex profile operators to cut the ends to whatever we want (the profile is the positive of whatever wacky cut we want). You can get pretty complex with it.
If you're super new to ArchiCAD and expect to do this with zero effort, you'll be very sad. Once you understand the process though, it's pretty simple and quick.
I think the log wall function of the wall tool is too limited for serious use.
