no need to rely just on Havok
better to utilize P.A.L. (Physics Abstraction Layer) while use as base physical engine e.g. Bullet Physics Library
this way You get easy access to cost effective (no license fees) OpenCL accelerated physics
You can also then interact Bullet with e.g. DMM and accelerate both via OpenCL
while Euphoria is nice
yet any proper realtime (semi/full)procedural animation blending would be enough ...
also there are similar middlewares around with better price tag ...
e.g. Locomotion for walking
the LUA part raise the question is if it's worth it
or why not look for something what may challenge LUA, one of candidates may be AngelScript
some may fight for good old Python
in the end just evolve SQF + allow direct C++ API linking to the application (hint VBS2Fusion)
C++ code build with Intel TBB/IPP/etc or Parallel Studio
combined with DX11 to squeeze max of todays PC platforms
the above is just example that You should always consider other ways