The InkPen smoothing is a bug I accidentally introduced in the 3.5.2 build. We are know about it and we're releasing an urgent fix very soon.
For your interest, a new feature I was working on for ArtRage 4 slipped into the 3.5 codebase and interfered with the InkPen (and Pencil in precise mode) smoothing.
When we do a release of ArtRage we are faced with a tough problem. We need to start work on the *next* major release immediately, but we know that we're also going to have to solve bugs (they're inevitable, despite our best efforts) in the previous release. As we're going to have to release the bug fixes for the current version and we'd also like to have those bugs fixed in the next version, we have to be very careful about getting the code mixed up.
For example, if I add an exciting new feature to the tools (which I cant tell you about yet ) but I also make a bug fix to the paint tools for the current version, I have to be very careful the new feature doesn't slip into the current version code, but that the bug fix is in both the new and old version of the paint tools.
Anyway, the fix will be available very soon - it's in beta testing now - and I'm very sorry for breaking the InkPen smoothing.
AndyRage's mantra for graphics engine code:
"Sure - how hard can it be?"