Yea I agree. I was only wondering if there are any restriction as to placing monsters on 'special spaces' (those with some token) on start, but it becomes apparent that there is none.
There is none. The 2E definition of an "empty space" is any space which does not contain a figure and which does not block LoS or Movement. Monsters must be placed on "empty spaces" during set up, and none of these tokens (generally) qualify.
I was also wondering if even though a monster sits on one teleport you could technically still teleport there then teleport to next teleport finally stoping on the one which is empty. Though after re-reading rules which say that you treat them as adjacent spaces the answer would be no, i.e. you cannot teleport to a place where a monster is located, right?
Correct. The monster doesn't technically block line of sight to the teleporter it's standing on (because of the special rules for "teleporter LoS") but you still can't move into a space containing an enemy figure, so you can't teleport "past" the monster to another teleporter.
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