SnapCreator does indeed manage and truncate your transaction logs in Domino.
Remember to place the Changeinfo folder on a drive/LUN other than the one you use the Domino/data or Domino/logs.
Also NetApp recommends to snapshot the Changeinfo seperately from the Domino/data triggered snapshots, I guess because after the snapshots have been taken of Domino, files are updated in the Changeinfo folder... You also set how long you want to keep your logs in the Changeinfo, (in your example it's set to 1 day), but I would suggest to set it to as long as you plan to keep your snapshots on the primary side.
You also need the Changeinfo folder and its contens when you restore files...
I have currently setup a few Domino Windows servers with FC LUNs via VMDK's, possibly the least "sexy" way to do it. The backups work as expected, yet the restore is all fiddely commandline.
I am not a Domino admin, but it seems that the SnapCreator plugin is focusing on the Linux/AIX version of Domino where you are able to use NFS, which makes restores from the SnapCreator GUI possible...
I would suggest you take a look at this document: TR-4009 as it describes all this above.