My advice is to not make changes to the DLL that are specific to Blitz3D. Most of his sales will come from non-Blitz users. ODE functions should behave like the standard ODE functions. Otherwise, you isolate "BlitzODE" from the rest of the world.
Arkon's wrapper was an extreme example of modifying ODE for Blitz. When you can isolate a chunk of code like this, it is really important to leave it with the standard functioning.
For example, I have a PureBasic dll that wraps almost all the PB functions. I thought about modifying it to make the functions more Blitz-like, but it really works better to just use the standard commands.
Arkon's wrapper was an extreme example of modifying ODE for Blitz. When you can isolate a chunk of code like this, it is really important to leave it with the standard functioning.
For example, I have a PureBasic dll that wraps almost all the PB functions. I thought about modifying it to make the functions more Blitz-like, but it really works better to just use the standard commands.