editing of poll script ?? (maybe a license issue?)

would it be bad if i "modified" the adv poll script?

i just installed it, but found i needed it to do more things (like, have different titles for each poll as they will be displayed in various places of my site) ...

well, one of the things i did was create new templates .... ok, fine ...

and i liked the popup feature for the results and voting ... BUT, i found that even if i set the templates for the poll to use my custom template, the popup, NO MATTER what would still use the "popup" template that was already defined when i installed it ...

i couldnt figure out why .. i could throw jibberish in my custom template, and it would still default to using the "popup" template...

finally, i figured out that in "popup.php" there was a variable that set the template for the popup to default to the "popup" template...

so i made a new file (called results.php) and set it to default to another custom template which did exactly what i wanted ....

so the question i have is, whats the license/useage for changing the script? am i able to make changes to the script at all? to how far? etc?