It looks like the post-processor that you've tried has support for arcs and is intended for more recent products like Cut2d/VCarve/Aspire. Photo V-Carve is an older product and it predates the support for arc moves.
If you have a Omnitech PP without arc support, you can try that one. Alternatively all the sections and variables related to arc moves have to be removed from the PP before Photo V-Carve will be able to use it.
I hope that this makes sense,