Can Scapple typing lag issue be fixed? (problem fixed!!!)

Finally, I’ve got it!
This problem would be fixed if you locate your uppermost note very below the “file name bar.”
Don’t leave margin(empty space) over the uppermost note.
Easy way: copy all notes to a new Scapple file and make new notes only downwards and never joom-in or out :imp: :imp: :imp: :imp: :imp: :imp: :imp: :imp: :imp: :imp:

Macbook Air 13inch
1.1Ghz quad-core

Scapple Ver. 1.30.4

over 80 notes
over 7000 letters in total

Under this circumstance,
Whenever I make a new note, huge lag starts with second line. (no matter how wide a note is.)

Is this issue caused by my computer?
my computer is not enough to run Scapple?
If I change my Macbook air to “iMac” or “Macbook Pro”, could this problem fixed?

or, is it just because I typed too many letters?
How about others?
Aren’t you guys typing more than 7000 letters in total?

I really need your help T.T