#8 Misuse of PX_PHYSTYPE_RB_PROXY enumeration

[Stephen Chenney]

In px_control.ms, line 549, we see:

if index == 11 then index = 8 -- special treatment for rb_proxy

This must be changed to

if index == PX_PHYSTYPE_RB_PROXY then index = 8 -- special treatment for rb_proxy

in order to be robust to changes in the enumeration.