Update:
I exported mm into html file and then dropped it directly into Leo.
Leo imported it properly,but instead of nodes/subnodes/etc I got a
HTML tree (Yes, its about a Dollhouse, planning to do that with my gf, dont judge me hehehe)
So next thing to learn for me is to transform that into Leo Nodes. (I dont want to come back to mm so I dont care about lossing information on it, sticking to Leo!!)
As with the rest, I added this "step by step manual" to my Macro tutorials list, which will import a HTML file then show the user how it can be transformed into Leo, and will point towards the information which must be changed for leo to change the way it imports, and some other neccesary things for users to quickly learn about importing. After importing my mindmaps and web bookmarks (which have all my needed resources) I will be starting to program the macro tutor.