Change image dimensions in flypage

Hi in the category layout the images of the products shown are from the folder which do resize the images to 90x90,i want the images to be bigger, is there a way to change the 90x90 resize or the whole folder?

Thank you very much

Hi,
you can change it in VM settings. Go to Components->Virtuemart then from left column choose 'Configuration' tab. Click to Configuration option. Then in right column choose 'Templates' tab and go to 'Thumbnail Image Width' and 'Thumbnail Image Height' options.

Thank you very much, 2 more questions
After the image there is the title of the product and then the short description, but it doesnt shown the whole description, how can i change the number of the letters that will be shown in the description?

And when i save my settings in backend the changes in frontend do change but after some minutes,is there something like cache which i can disable?

Thank you for your help