I think Stripes is onto the right track here, when the plugin is loaded and room entry is attempted it crashes, I will be looking deeper into this but i suspect that the root cause is down to text processing as nearly all the chats have color messages and this chat client seems a bit bereft in this area.
[update]
It seems that the link plugin only fails when the kurukuru plugin is also loaded, I tried them one at a time and noticed it was possible to see the link plugin working fine when kurukuru was not included.
Might be another helpful clue
(PS: I tried grabbing newer plugins from the nushi 2.8 but that didnt seem to help in this case.)