Help re: Formulas Contained in Column(s) N and O

[ctx700nd]

Formula in N should create as many rows with a student's ID name as there are courses selected in column(s) B through M, and the formula in O is supposed to transpose the courses selected by each student. It only works for first 5 students and first 5 courses selected. Can anyone fix it so that I can use it with 1000 students and all the courses shown for each student?

[Rizky]

Perhaps something like this? Using Helper Column to avoid complications, and all is array formula.

Regards
Azumi

[Beamer]

I had worked out the 1st column without a helper column but got totally lost when trying to do the 2nd column.
When I checked back here I saw that Rizky had posted that awesome spreadsheet and since I'd already got column 1 to work I stole his code for column 2
I think Rizky's might still be better (probably faster), but mine doesn't need the helper column.
Use and modify as needed I guess.
I hope one of these will work for you ctx.

[ctx700nd]

Thanks so much to all for your input and suggestions. The solution worked. Many, many thanks.