The camera issues sound very weird to me. I can't think what could cause the error messages, but at least you've got it working now.
It looks as though you can fix the small grid by going to 'Display', clicking the box next to 'Grid', and then increasing the 'Length and Width' value.
As for the masts not showing up... it seems I underestimated the number of polys this model has. Over 169,000?! That's quite a lot more than most of our highly detailed ships!
The problem here is that a GM file won't export to OBJ format intact unless it consists of less than 50,000 polygons. This can sometimes be fixed in TOOL, by using 'Edit Scene' to cut copies of the model into its individual components, and hope that each one is worth less than 50,000 polys.
However, what really concerns me is that the masts are not showing up in TOOL.
That's exactly the same file you showed in GM Viewer, right? If so, we may have a problem similar to the Soleil Royal model.
I can't say that for certain unless you send me the model to take a look at. It would be easier for me to tell that way, rather than trying to describe what to do.
If that IS the case, then the only feasible solution might be to modify a texture to hide the mast stumps instead.
Even then, we rely on the UV mapping allowing that to be done without also hiding other parts of the ship.