Typically, yard tracks, industrial spurs, and sidings are 'depressed' compared to the higher speed mains nearby. That is so that loose rolling stock that begins to roll can't climb up and foul the turnout or the main (although often there are derailers placed before the turnout linking the siding to the main prevent such fouling). So, if you can build a gentle transition up to the main with the roadbed, that would be more prototypical.
I can't tell what the problem is with the hand-rail, but if the nib is still in place, they are usually meant to be just a pressure/friction fit in the hole. In any case, if you must glue, just use a tiny drop of CA or MEK. The problem will be that if either type migrates outward from the insertion, you'll get a frosty look there or a shiny one in the case of the MEK.
