Yes, that's all it takes for main Mint. That's the USB configuration I use now. Note again, this will not work for LMDE.
Thats great. and so it will just grow on-demand until the casper-rw partition is filled? thats better for flash memory than a virtual disk with the free space inside of a file. the flash memory controller see's that free space as taken. If any boot problems after this, flag the original FAT part as the boot partition.
I have a tip for those who still use Remastersys to first customize a system, then usb-creator-gtk to make a USB with a FAT 4 GB persistence file.
When you first make your USB, write all zeros to the virtual free space*(see below dotted line). Then go into another system, copy casper-rw onto another drive, and RAR the casper RW file into a rar like restore.rar, with compression method set too "Good" and a 3% recovery record, (ECC for file corruption)
delete the copy of casper-rw that you moved to the other drive to compress, then Put the Restore.rar on the root of the USB. You now have a Factory Reset / system recovery file, to reset the USB back to its original state , akin to those recovery partitions that come with windows computers. To revert USB back to first-created state, UnRAR it with "extract here" and press Yes to overwrite existing files. Or you can experiment within the USB its self to see its capable of over-writing its self with the unrar command in a script.
I did this and my 4 GB casper-rw file is compressed to just 147 MB due to writing zeros before shutting down & compressing in another OS.
* - how to write all zeros to the free space
Go to home folder, and Shift + Del the wipe_file
shut down immediately, go into another system, and TAR or RAR the casper-rw which will now compress a lot due to being mostly zeros. So small, that the backup fits onto the root of an 8 GB USB , if the initial system squash fs is under 2 GB and the persistence is a full 4
These instructions are for backing up the conventional casper-rw 4 GB persistence file into a tiny file only 150 to 250 MB. You can give bootable USBs as gifts and tell the person how to save bookmarks regularly and what to do to reset USB back to state of first boot.