I would maybe add on bottom of Nests list some helper buttons to add most common nests, like uppsrc, bazaar, reference, etc... So if you start with blank new assembly, you can just click few times to have basic configuration set up, then you add the extra custom nests.

IMO the existing assembly setup dialog is somewhat cumbersome and unintuitive

I redesigned it around an ArrayCtrl (with row-moving (up/down), and multiselect (for deletion).

I think, that this may depend from experience of concrete person. There is maybe some purpose for current design. For example, possibility to copy/paste needed string(s).

The current "Assembly setup" dialog allows to configure "Package nests" with using a single EditString.
The ">" button is multi-functional for "Package nests", which allows to:
- Add path for new nest, if cursor after last ";" character or nests are empty
- Change path for selected nest (e.g. between ";" character(s)) otherwise

I think, that possible to implement what you proposed for "Package nests" in a separate window, which invoked on some FrameRight<Button> click (e.g. near ">" button). Attached some patch as example (based on 11983 revision).

Did you see the first screenshot, or applied the patches?

Instead of using a single EditString, it uses an array with per-row directory selectors. Namely, ">" buttons.

I just tried to compare current and new proposed design, based on some possible use cases.

I guess, there are other people who may decide about such changes, as well as express their opinion about this, if needed.

I do not like the new UI - it doesn't look great and it is a little bit overwhelming. I believe we should keep it like it is and add the possibility to display nests array in separate Window. The nest still will be displayed as EditString, but it can be modified as ArrayCtrl. I was thinking about adding buttons like we do in Android builder:

For me the button associated with path selection should be always visible not only in edit mode.

There is a bug at least on my machine (Latest neon). When the list is opened you can click on it and the empty entries will be created. We shouldn't create new entry where there is no content associated with it.

IDK. If this is going to be changed, I would rather like the original proposal (list of directories in the first dialog), with option to write it as text... (or maybe with both text edit and list - harder by doable).

I have not checked the patch yet, but I would like to remind that the order is important and the first nest is important. Therefore, drag&drop (and maybe up/down buttons) for ordering is essential. Replacing directory is not. Remove/Add is enough IMO.

For me the button associated with path selection should be always visible not only in edit mode.