Two things that I find distracting:
1) Turning drawing objects or presets On/Off makes the screen jump
The image I currently edit in the main window jumps left and right because of the tool settings popping up and taking up space. Maybe they could be made to overlap to the left instead of shifting the content back and forth? It's easy enough to zoom or pan away from it, should the settings really cover up important content. Or maybe it could be restricted to the AutoFit checkbox - an enabled AutoFit would make it jump, if disabled the settings would overlap, keeping the image still and stable.

2) No shortcut for object selection mode
I know I can make it switch back automatically every time I use a tool. But this is not what I want, some tools are great to be sticky. But every so often another object gets in the way and that always requires to aim at the tiny button and a second later you travel back there again to pick up where you left off. Heavy editing results in a lot of mouse travel, especially on a large HD monitor this amounts to quite some mouse mileage, your attention is continually taken away from the hot spots to aim for the tiny select-icon.

Suggestion: Ctrl held down = temporarily activate object-select tool
To accommodate this behavior, other shortcuts would have to be streamlined, such as Ctrl-drag line tool. Actually, if all tool-modifier keys could be made to respond to say, SHIFT, it were easier to remember. Resizing a rectangle proportionally would be Shift-drag (instead of Alt drag now) etc... Holding down Ctrl would temp-activate object-selection, holding down Shift would activate the special mode for a given tool (resize proportionally, draw horizontally/vertically, etc)

I always manage to create them in the end, but getting there is never a straight path.
Could someone please correct my workflow:

1) I create a new node, a "real" one, I enter the path to the exe etc. All fine, never experienced any problems

2) I make a note of the ID for this new node.

3) I drill down another branch to create another new node. I use the type-dropdown on the right side to assign the type "link" to it. I enter the ID of the source node from above, ....  and then what?
Any other mandatory entries I need to make?
Sometimes I enter a caption, but it seems this is not necessary. I always click Save.

I leave the config dialog, my menu shows the functional entry from step 1 - but none of the link nodes I created. I enter the config dialog again, and do nothing different, really, other than repeating step 3 - and on these subsequent go-arounds I have always managed to somehow generate the link node. Just wondering...

It will list all existing files, but upon clicking opens only those without spaces in the name.

No big deal, I can simply Ctrl click to open the containing folder. But it were more comfortable not having to take this detour.