Perhaps this is the wrong thread and if so

[handrawn]

there is only one program per version - it operates in trial mode until you have successfully entered the key [serial number] then it switches to full mode

version 6 is now 12 years old; getting it to work on windows 10 is not guaranteed- I am pleased you were able to do this; in my case there were registration issues, but this may have various causes including simply the version of window 10 in question

with a program this old I would install it in compatibility mode and as administrator

it is possible that administrator rights are blocking the registration of your serial number when you enter it and so the program remains in trial mode - try running the program as administrator if you have not already done so [right click and select from popup menu]

I do not think with a program this old that the serial number or activations would lapse, nor do need to be connected to the internet...