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Yes the primary mirror in these scopes is fixed in place, but there is a little trick that can help. By loosening the three screws that hold the primary mirror cell in place just a touch, the cell can be tweaked a little to improve collimation, and the screws are then re-tightened.
There is SOME repositioning possible with the secondary, but this is limited too. Remember, they are made CHEAP, so to spend too much time on them at the factory is not economical. Most secondary mirrors are just set eye-balling to give some sort of good-enough reflection of the primary back through the focuser. Thing is the position of the single arm can be set too high (or low) with the secondary holder mechanism not having screws long enough to give the secondary mirror enough travel to best collimate it with the focuser. If set too low, then nothing you do with the secondary mechanism will improve things. The only other option here in both cases is to re-drill and re-position the arm holding the secondary. My FirstScope has the secondary's arm set too high.
These scopes are not made for dedicated amateur astronomers. They are considered toys that will be discarded and forgotten quickly. So don't expect too much from them out of the box. Another reason for the poor eyepieces they are supplied with. To fabricate them to the standard we expect makes the labour involved too expensive - you are getting what you pay for. They all require considered TLC to trick them up to their full potential. This potential can also be compromised by they way they've been put together. Up to you then as to how far you want to take the modifications. But if they are modified as far as their design allows, and as far as your tools allow, they can be quite an effective little instrument.
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