Im baltics, if your Z is issued in HK, it isn't issued on mainland, is it?

No, it's not mate, your spot on. But I don't foresee any problem at all, as I have always been able to get a Z in HK when possessing the invitation and psb document with the all important red chop, mei wenti. The only time I wasn't able to was the olympics, but that was the same for everyone AFAIK, wasn't it?

With the Z from your homeland or HK as you claim is still ok, you are to get an RP on mainland.

I'm getting the Z from HK, and will get the RP in Zhejiang province. Outside Hangzhou. I'm not sure about Chongqing, nor Guangzhou, especially now the asian games is fast approaching.