Installed on 4.2.

Entered one forum ID to test it out on and it brought up no polls. The result is blank

i just changed dependency version to 4.9.9 as without it you can't install this mod on vb 4.2.0 +
check vB default skin ? (is it also messed up)

Remove Poll Sideblock from Forum Block Manager, if by chance it is not removed after uninstalling the mod.

Run clear system cache under Maintenance.

I did and it still comes up blank

ok.. do you have any poll inside that forum ?
and set threadid to '0'

I have
Fetch Latest Poll From Forum: 56
Fetch Poll From Thread: 0

And I just created a poll in forum 56 to test.

FYI I just tried out POLLID and that doesn't work.

I'm using the default theme for VB4 as well.

problem with 4.2 : twice or more poll are displayed into the side bar !

clear the cache or wait for few days will be releasing Ajax Poll SIdeblock.

Getting double poll blocks as well. Looking forward to your Ajax Poll Sideblock.