Sure - it's happening because you haven't taken control of when DBPro shows you what has been done so far.
At the top of your program, use the SYNC ON command - that tells DBPro that you are taking charge.
Then when you've done everything you need to in your main loop, use the SYNC command to tell DBPro it's all done - everything up to that point will be displayed.
sync on ` I'm in charge!
sync rate 60 ` Stop me drawing any faster than this
make object cube 1, 1.0
do
yrotate object 1, wrapvalue( object angle y(1) + 1.0 )
text 0, 0, "Cube angle = " + str$( object angle y(1) )
sync ` OK, I'm done - you can show it now
loop