1)I'm in your identical situation ! I have not a lot of experience but I have upraded my Perl to 5.8 whtout any problem. If you wont to use Perms you can't 'cause this module was buid for 5.6 and not maintained 'till now.
2)I'm very interested about your work 'cause it seems very similar to mine and I'm sure you are more experienced coder then me.. want you exchange some piece of code with me? I have some script in progress that scan and modify IIS to grant some site the asp exstension.. virtual dir and a rudimental fixer of no-synchronization of identities of IIS..