Hi,
This is very custom question. The best would be to convert everything to ASCX or HTML. In Kentico, there is a web part available called XSLT viewer in which you can use the xslt transformations but I am not sure if this will cover all your needs. Also, you will basically just copy the problem to another CMS so I would recommend to consider re-designing the architecture from scratch and covert the data to other format.
Best regards,
Juraj Ondrus