DB48X: HP48-like RPL implementation for DM42

[grbrum]

Hello Christophe, I love the implementation of CST. Thank you very much for that.
I also love that you made it possible for different CST within each directory like the HP48.

I don't have a HP48 on me while I am traveling for work, but if I remember right, I could store the CST menu anywhere (directory), and if there was no CST variable in current directory, it would use the CST menu of the parent directory. I may be wrong. I tried this on the DB48 and it only sees the CST in current directory (this may be accurate to the HP48 behavior though).

I would like to please request the following enhancements:

- Would it be possible to have a "blank" command to put in the CST variable? basically to have an empty field in the CST menu?
{ Name Value "Blank"}
I am playing with the functionality of having shifted option for CST menu, and I think it is just easy to have the relevant menu items on top of each other (ie A, A> and >A) in CST menu.

- Would it be possible to implement this from HP48 manual page 30-3? "Also, instead of storing the list of objects itself in CST', you can optionally store the name of another variable that contains the list."

Finally, doing tests with MENU and TMENU I noticed that now I have a 1 in a box in top left corner, I could not find documentation about this, is this a flag that I accidentally set?
thank you.