This issue is already heavily bug abused on a daily basis by numerous rangers (see appeal) and thus needs to be solved ASAP. Sorry for sounding overly dramatic but this is literally killing every tower fight vs hibs with 99% of the playerbase not even knowing what the hell is going on and why they just die. If this knowledge spreads further then all tower fights will devolve into scout/ranger/hunter groups sitting in the basement killing everyone above (a thing hibs already do with their ranger groups).
If this texture issue can't be fixed then archery indoors needs to be removed completely for towers (in the meantime). This is unacceptable in the current state.
Update1: I did a quick test with a scout (thanks for the help!). We found 4 holes that are 100% shoot-through. From the basement to the lordroom or the floor inbetween. If you stand in these places the enemy archer in the basement can 100% hit you with all his arrows, with an assist of 5-6 archers this is an instant death. Just "driving-by" these spots also seem to be enough to let the shot go through, even if you just ran over that spot for a split second.
Here are the 4 spots I found in the quick and dirty tests:
Oil level 1:
Oil level 2:
Lord room 1:
Lord room 2:
On top of that I also got shot multiple times simply running around on the different floor levels and up/down the staircases between oil-level and lordroom. It seems to happen due to glitching through the floor (extrapolation to reduce visible lag?) as the scout reported seeing me appear at the basement for a split second. Or due to multiple smaller holes that I couldn't pinpoint exactly in this small test. (by "drive-by" shots I explained above)
I'm sure there are plenty more holes where the archer in the basement can hit people above him in the tower, probably depending on his own position and his target position. This was just a very quick test and I already managed to find 4 definite holes and plenty of random hits.
Update2: Here is the video of the test, sorry for the bad quality, I hope it is good enough to see the random hits I got running through the tower. The scout position didn't change the entire test and is showcased at the end. (sorry I forgot to start the video at the beginning)
Video is currently uploading but here is the link already: