I installed the mambot, set the settings, but whenever I add the gallery tag to a content item the content item fails to show and instead this error is displayed.

Fatal error: Call to undefined function: imagecreatetruecolor() in plugin_jw_sigpro/sigpro_engine.php on line 138

uninstalled and reinstalled 5 or 6 times.. its still doesn't work

No I do not.. I just bought the pro one.. I never even tried the free one...

Do I need it?

Could you please ask me all the questions you want to ask in one post???
It's been one week since I bought this plugin and still IT DOES NOT WORK.

It is not hard to ask these questions all at once, have you tried reinstalling, do you have SIG installed, is it on a test server?  I can answer these questions in 5 seconds, you can answer in 5 seconds, why should it take ONE week.

I am installing the mambot on a fully functional, 100% live website.  It is not a test server, I have tried reinstalling 10 times now, and I never had SIG installed.

Please find a way to fix this or refund my money!

My hosting company, hostmysite.com says I am already running GD 2

From my hosting company.

"GD (Version 2.0.15) is already properly running on your server there is no need to install it again."

Since you don't offer refunds can you please figure out what is wrong with my script? Otherwise I just completely wasted my money buying this script.