Download Ubuntu or Linux Mint and use GParted or use GPArted Live.
Also, when you deploy your image to make the changes and recapture for new image you can copy your OSD script, and rename it. Right click the new copied script, select Advance Edit, scroll down, find and delete this line"REMEXEC45=ldrun diskinfo extend_last_partition"
rename the remaning lines to 46, 46,47....
Save and use this script when you need to deploy the image to modify it.