Apparently X11 was not installed, thank you for the heads up.
Since I don't have the OS installation discs it took my time but eventually found a stand alone installer for X11 2.4.0 and seems I have ...
Thank you for the reply, I thought X11 was installed on 10.5 and up automatically, will check that (I hadn't done the OS installation myself this time)
Today I purchased UVlayout Hobby version and received my key for the activation shortly after.
After downloading and installing the most recent .dmg; the software did not start properly.
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