Installing WM6.5 SP2 + EDI version 6.5.2 on multiple instances Windows box

Dear experts,

I failed to find something similar in upgrade topic, so please excuse me if it has been already discussed.

I’m trying to install SP2 on WM IS 6.5 and EDI 6.5.2 using downloaded image option.
The problem is Installer (versions 6.5, 7.1, 8.01) tells me that the files are already installed and it’s going to do only reconfiguration (according to the about page of the server SP2 is not installed and EDI has version 6.5).
After the second of work it’s finished and nothing is done.
All the versions still the same, nothing is copied to the upgrade directory etc…

Maybe the problem is I have multiple ISes on the same hardware box.

But how in this case I can install the SP to the chosen IS?
Probably there is something else…
Could you, please, advice me what i can check, to do etc?

PS: I’m NOT mistaken in home directory provided in the Installer dialog =)