starting with 2.5.6.49314 you have some tools.
Saved Games/DCS.openbeta/Config/autoexec.cfg:
sound.editor = true
will provide you with 2 buttons:
1) to reload SDEFs. NOTE: existing game objects won't be affected. You need either to respawn (if modding your aircraft) or restart the mission (if modding AI units).
2) to purge wave files (both ogg and wav) - this will flush unused samples from the memory so when they are needed the engine will pick the fresh ones.
Not ideal, but still helps.
you have to install the module. It is included in the dedicated install, but not on the regular one.
bin\DCS_updater.exe install SUPERCARRIER
DCS will complain when run w/o --norender option, if you don't own the module, though.
this is weird. the only change in the server browser was lower rate of per-server requests to fix the incorrect pings issue on slow links. other than that - no changes. can't replicate this internally yet...
Automatic IP range scan most probably.
DCS needs the port to be open for both TCP and UDP.
Standard "open port check" services can check for TCP only.
In your case, most probably UDP packets do not get through.