Development Questions : Can it be use to help build/fix codes created by others

Lets say you got permission to add-on to a modification, then can you use this forum to develop and or improve add-on/modification.

Another is you find a flaw e.g. security hole, then can it be release as a patch (most likely needs to be reviewed prior to releasing it) or have a discussion in how to fix said add-on/modification.

It seems that it is, but have to make sure.