Hi Fishbowler!
Of course you can publish/post links to your tools here. I guess a lot of users can benefit from you tools. Regarding your questions:
1) I think the only person who can answer this question is you. You can open the source if the code is written by you alone. If you use 3rd party code you may need to ask for permission from the originator.
2) Same as question 1. As long as you don't violate any copyrights, go ahead and post your tools.
3) I am constantly extending Royal TS. Chances are, that these or similar functionality will be included sooner or later in Royal TS. Right now I am working on a new file format which should make these kinds of things easier. If you cannot host these tools yourself, we can find a way to host them on my server and post a link to these tools here in the forums.
cheers
Stefan