10) Do I need to strip & clean the Bolt? -
The answer is - Yes, you do need from time to time to disassemble the bolt and clean it carefully.
The bolt is subjected to contamination may be less than the bore, but still it is. Generally it is a good idea to strip and clean the bolt every 500 shots. This is an approximate number and depends on several factors, but mostly the ammo type used in your gun. DE manual advises to remove bolt after every shooting and clean it. This is about bolt surface, but bolt internals parts are getting dirt, powder residue and fouling just as well.
There are several moving parts in the bolt (ejector pin, extractor claw, both have springs and holder pins) plus the firing pin moving through it with its spring, plus the bolt itself is moving inside the slide. As we see that's pretty much moving parts together, so it is very important to keep it clean & well lubed, where necessary. Otherwise, it may lead to serious problems with gun proper functioning, such as: failures to feed ammo, damaged or even broken parts, like holder pins, etc.
Disassembling the bolt is not a difficult operation, just usual precaution measures are necessary, like wearing protective glasses and watching some parts, those tend to 'fly' because of being under spring tension. There is a special section dedicated to this question in DE Cleaning And Maintenance page - DE bolt disassembly & cleaning.