Hi,
If you have at least PHP 5.3.10+ - you can try,
but remember to make a full backup first. We are not producer of VM so we can not give you any warranty!
p.s.
Almost all our supported e-commerce templates have been updated to latest VirtueMart release and files are available in Updates section at gavick.com. So also before (not after!) check if new (updated) version of template is available.