I have to click on the NPC's multiple times for them to eventually respond.
I have never witnessed this problem before but if for you clicking on a npc doesn't work try to walk next to it and press
T on your keyboard. You can also target a npc by pressing
N and then you talk to it with
T. You can also right-click and select
Talk.
It takes forever to enter the next room.
This might be network problems. Even with a "strong" internet (fast speed) like you say it can still drop packets if the line is of bad quality. Please run a test on
http://www.pingtest.net and
http://www.speedtest.net and tell us the result.
Also, open the
Debug window (F10) in manaplus and go the
Net tab and tell us the ping (ms).
When trying to kill the maggots on the first quest, my character kills a few and then doesn't attack them at all.
Again, network problems is the most plausible culprit but the server also has a bug with the "walk path" which makes mobs sometimes appear to be in a place that they are not or to suddenly jump from 1 tile to another (desync).