DipTrace can create slot holes in NC drill format for TH pads with oval holes. The problem however is the slot holes will be transferred into the same NC drill file with plated holes. We will consider extending properties of mounting holes to make slotted mounting (i.e. non plated) holes.

Please run "Verification -> Check Net Connectivity". It will report the list of broken nets. Select each error to see details, i.e. list of isolated areas. Then find each isolated pad and investigate why it's not connected. You may need to change copper pour properties or create an extra trace, etc.

The basic recommendation for selecting multiple items one by one is holding down Ctrl key as in most Windows programs. But I don't see difference when using Shift key instead because selecting a range of components is not applicable in Schematic.

The question itself about difference the shift and ...

The search works by component name by default. If necessary, you can add more parameters into the filter, such as pattern, value or anything else.

This is one of new features in version 5. Find it in "Tools -> PCB Calculator".

There are multiple libraries with capacitors in the latest version (5.1.0.3 at the moment). The names of components in "Capacitors Aluminum SMD" library (and many others) are manufacturers part numbers. For example, UZP1HR33MCL1GB. Knowing the part number, you can find the part on Digikey, Mouser or ...

Thank you for the report but I have never seen the issue. Could you create screen video to show the problem and share on the forum.

You can import Gerber and drill files in PCB Layout. But this won't recover original PCB design in full. You will get many shapes, pads and holes but won't get them as components, nets, traces and copper pours.

Thank you for the feature request.
"Depending on board" trims or expands copper pour regarding on if you created the copper pour bigger or smaller than board outline.
"Snap to Board Outline" option does the above changes automatically once you edited board outline.

In order to get correct BOM and Pick and Place files, it would be better to have mezzanine connector and studs separately instead the composite component. Further in PCB Layout you can group them to operate with items as a whole.