porting old fasm programs encountered this feature /isn't it bug?/
When there were lots of "return" directives in procedures, i decided just to equ them: return equ ret -> and got it assembles as simple retn in procedures no epilog cleanup, but using fix: return fix ret, i got correct assebling.
So why equ replaces "return" after "proc" macro parsing not before? Is this right sequence of processing?

You should try to avoid using fix. It's use is not very clean for most cases.

fix helped me while equ not. Fix has higher priority said in manual, but why equ works so?

You have to examine your code to see what macros and other equ's and fix's are doing.