QUOTE
I can`t register "uiso86pe.exe", but "uiso86pes.exe" accepts my registration code.
So, my question is - must i download new versions of UltraISO ONLY from the URL provided at my registration email ?
For first time registration, you MUST re-download and setup the full version software from the URL given, no need to uninstall the trial version.
When a new version is available, you can get latest version from links on download page, setup it and keep registered with your registration information.