Cannot use cross-section data with regular DSMC

[BillyTheKidPhysicist]

I'm not sure if this is a bug, but I cannot implement cross-section data between DSMC particles. If I have two species, 1 and 2, I can produce the expected behaviour of collisions between species 1 and 2 if species 1 is a background gas of density n with provided cross section data. If instead I make species 1 DSMC particles of density n there appears to be no collisions of any kind, even elastic. I also have to circumvent the error that this cross-section collisions are only implemented with background gas. The documentation states "It should be noted that this model is not limited to the utilization with MCC or a background gas and can be used with conventional DSMC as an alternative chemistry model". This leads me to believe I should be able to use the cross-section data with DSMC particles. I am ensuring that I am using the flag UseCollXSec=T for all species in the DSMC.ini. Thank you very much