No longer multiple selection in Landscape Tile import explorer window

That is weird.
I can no longer select multiple tiles in the explorer window.
I did it with sucess and multiple selection in the past (last week) following this tutorial A new, community-hosted Unreal Engine Wiki - Announcements - Unreal Engine Forums

At landscape import Point 6, i can no longer select multiple tiles.
I can make a fresh project, tried three different Engine Versions, all show the same behavior.
Tried so much, the last two days, nothing changes.
For example, when i import assets i could select multiple meshes, like i need them.
There (explorerwindow) i can even drag a rectangle for selection, in the LS-import not.
One day i imported an island to a project.
Next day i tried to import an advanced islandversion and then i could no longer select multiple tiles.
Example for tilenames “insel_x0_y0.r16” “insel_x0_y1.r16” “insel_x1_y0.r16” “insel_x1_y1.r16”
But i can not even select multiple tiles, which i imported last week with sucess, because of no multiple selection possible.
If i copy “insel_x0_y0.r16” “insel_x0_y1.r16” “insel_x1_y0.r16” “insel_x1_y1.r16” into the part of the LS-Import explorerwindow, where it shows the name of selected file(s) and try that, then only first Tile is imported.
I needed the last two days, to be sure, that i am not feeling like a complete idiot, after opening this thread.
I even changed my mouse and keyboard.
Best regards

Deinstalled UE4, fresh install on same pc, tiled import (multiple selection) not working.
Fresh install on old Laptop, working like expected.
All i did on the not working system was installing the ArchViz template from Koola and the destructable wall thing.
Nothing edited at engine.ini, by my self.
What can i do? My working system is the only one, from my systems, which can handle UE4 proper(performance).

Learned substance basics, only to get to the point, where i recognize that substance could not handle UV on modular assets well.
Then i learned world machine basics, to make a nice island for my ArchViz stuff.
Now that thing with no multiple selection.
Close to get frustrated. :frowning:
My sys is a i2500k with GFX 560Ti and 8 GB DDR4 Ram OS is Win 7.
I have no reason to update my system/ buying a new one, still good enough for me.
Sure i could buy a new one i7, but when i encounter the same problem with a new system, which i bought only for UE4, then for sure i would cry.
I am not rich and my Kids could use the money better, then i am in the need of a new sys.
My grandma blahblah
Sry kidding.
Best regards Stefan