Go for it absolutely zero issue at all on the same IP even with interlinking those are microscopic. Flash Games....Construction sites? You got me interested with that combination what are you working on? A hybrid of the 2?
My construction site is for my construction business and the game site i had just puchased the game script and published it on one of my parked domains. I have a few others on there though. the adsense link in my signature is one of them too. I plan to build that site and try to get it going good eventually. It is just one page now.
How about if i have lots of subdomain and in menu list the subdomain link to eachother in everypage of my site.. Will it consider link scheme?
the idea is like websitebaker.org if you take a look there. they are using same IP address.. So websitebaker is not good for inbound link example?