Question about the map editor (limits on certain items).

Hello, I really need help with this! I'm using the HotA version of Heroes and creating a map in the map editor. There are many limits on certain items. For example, on Pandora's Boxes, events, and Trees of Knowledge, etc. I wanted to ask those who know if there are any limits in the HotA version on monsters, resources, and artifacts? I'm creating a Huge map and trying to fill it with as many interesting events as possible, and I'd like to know in advance if there are any limits on these things. And is there a limit on the map size (e.g., can a map not be larger than 1 MB)?