small changes to virtuemart site

I need a few changes and tweaks to a Virtuemart site: 1. I need the site superadmin to get an email notifying when an item is out of stock 2. On the product detail, the little arrows to add or substract to the quantity before adding an item to the cart, dont work 3. On the admin, when you upload several images for a product and then you try to view those products images, you only see the last one you uploaded. 4. I would like to make a tax choice to be the default 5. Some of the headings in the VM admin are too large 6. I need a way for the superadmin to be able to update a product's stock from the frontend I will give you the URL and screenshots showing you each point on PM