I'm a bit unsure about infestation, which ones are glitches and which ones aren't.
I got some screenshots and it would be great to know which ones of these are considered being glitches.

Thats a very useful tunnel from warehouse to ore! fucking lazy aliens cant even run 5 meters

Infestation was intended to be able to dynamically climb and adjust to changes in Z axis. So the times it forms a "stair-stepping" up to higher levels aren't necessarily bugs, but visual annoyances that seem inconsistent.

As a result, I think we have to deal with infestation through walls. It's probably something that allows the infestation to "jump" empty spaces if they're small enough, so if a wall is too thin, the infestation will go through the wall. We have these problems on many maps and CAN be abused. In the ENSL, however, it is illegal to abuse infestation through walls via echoing whips and such.

Basically, all of them are glitches and bugs due to the maps. However, what the NSL rules state:

"(a) Players may not:

(i) Intentionally place structures in places where it is reasonably clear that the structure is out of the bounds of normal play on a map (For example, on top of wall geometry).

(ii) Place structures on infestation originating from a cyst, gorge tunnels, or contamination on another side of a wall."

This is really up to the Referees interpretation during one of your matches. From my view which does represent only my own thought, other referees can think differently: the infestation originating from this cyst on Docking falls into this category. Other screenshots are more difficult to assess but I would say don't do it either way. It can be interpreted as a willing bending of the rules. You might report those bugs to the CDT though.