On Sat, 30 Apr 2016, Nikolay Sivov wrote: [...]
Regarding quotation marks, it's really up to target language to use one of several styles of quotation marks and quotation formatting. Original English text is only a reference, not something to follow.
User guide you mentioned, mostly tells to omit quotation marks (p. 58), and use straight double quotes if they are necessary.
The fact that '«' and '»' are missing from default keyboard layout is unfortunate but can't alone be a reason not to use them, if traditional typographical rules tell so.
On page 85 the user guide doubles down on their recommendation to avoid quotation marks, but also seem to recommend straight quotes, at least in the context of placeholders:
| Placeholders are often surrounded by single or double quotes in the | English source text. Quotes should be avoided in the Norwegian Bokmål | software. If they are needed in order to clarify the string, use | straight double quotes.