I have 6.5.5 (64 bits & 32 bits) , 7.0.7 (64 bits) and 7.5.20 (64 bits) at the same machine and another machine with 6.5.5 (64 bits) and 7.5.20 (64 bits).
No issues here.
I have 6.5.5 (64 bits & 32 bits) , 7.0.7 (64 bits) and 7.5.20 (64 bits) at the same machine and another machine with 6.5.5 (64 bits) and 7.5.20 (64 bits).
No issues here.