Hi,
After giving the command to change layers, I think there would be new window pop up and that window might be out outside of screen if your are using tool first time. That's you might think that screen is freeze. please look at edges of your screen. you might found window and it needs to be drag into middle.
I hope, it works.

Hi,

If you encouter this kind of freezing, this can be because a mask windows is open somewhere, in this case normaly the cursor change to be a "loading circle", this is a way to know allplan is waiting for an answer. If you can't find the tool, please try the different possibility to validate or escape the command in waiting.

1°) Press enter from your keybord to validate the request.
2°) Escape or quit the command by using the "escape" icone on your keyboard.
3°) you can use windows shortcut to display the tool again in you screen, by for example click on "Windows + right or left" to move the open dialog box to the screen.

If you still have the issue. you can call the technical support to have a look on the issue.

HINT: i'm not sure if you were talking about changing "drawing file" or really layers

HINT: for the layers, it's possible to activate the "trace"/log in allmenu and maybe one file for the layer is missing so the program hang.

BYe