These kind of go hand-in-hand, unless I'm missing something.
Right click on a PDF file, select Properties, then click on "File Type Options". In some cases you'll find a list of a bunch of apps in the "Application Preference Order" section, sometimes there will just be one.
If there is only one, hit the ADD button on the right side and pick the app you want to use to open that file type.
If there are multiple entries, check if the app you want is listed. If it's not, use ADD as above. If it is, select it, then click on the "Move Up" button until your app is at the top.
Whichever app is listed at the top in there is what Krusader will use as the default app to open that specific type of file.
Hope this helps.
Alex.
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