Image Resizing loses metadata

Help trying to set up a stock photo site with sell media plug-in to license my images with e-commerce. Created a sandbox paypal acct to test what my customers would get with download.
What they re getting is resized images to 72 dpi and no metadata info with no copyright anywhere.
Sell media support says its a wordpress problem.
Searched and wordpress forum says use imagemagick to resolve the issue.
Now I can’t upload any images- there is an error.
I am guessing it is because sell-media was made to use GD not imagemagick. How can this be fixed?
Can someone give me advice on what to do and if this is solveable or should I try another ecommerc plug-in such as next gen or is this problem accross the board?
Help save me some time if you ahve already dealt with this and give me some answers please!
THX