Fundorin,
OSCII-bot gives 1024 "string slots" and named string variables that can be used more flexibly for storage for the LCD display's contents than [] style arrays & memory offsets
See the "strings" section of
http://www-dev.cockos.com/oscii-bot/oscii-bot-doc.html
and this (jsfx) thread on same topic
https://forum.cockos.com/showthread.php?t=132630
There's probably some JSFX EEL2 code examples to be found too using strings like this.
Good luck with Sysex!