ROM Toolbox claims backups are blocked; how can I work around this?
I got this response from Koush, the developer of ROM Manager:


  ClockworkMod recovery is open source. However, the hooks that ROM Manager uses to automate backups by hooking into ClockworkMod Recovery are proprietary.
  
  I have told other developers, if they wish to use the ClockworkMod Recovery hooks, they can do it in the following ways:
  
  1) Build, distribute, and support their own version of ClockworkMod Recovery, so that I am not responsible for the maintenance of it.
  
  2) Use the ROM Manager API, which requires a ROM Manager Premium License.
  
  The user can ALWAYS make backups manually in recovery, without a Premium license.
  
  Basically, the issue here is that developers are relying on me and my open source work, which I maintain, to build a competing product to my paid applications. Essentially undercutting me by relying on me developing 90% of the product for them.
  It seems pretty silly for me to continue maintaining and distributing something that directly competes with my income, so I put a stop to it.
  If they want to build a competing product, they will have to go through all the hassles involved with building, distributing, and supporting recovery images.
  
  So, no, those other applications are not "blocked" from creating backups. They are just being lazy, and not actually building/flashing their own recovery image. Nothing is preventing them from building a ROM Manager clone, if they really wanted to. They are just avoiding doing the hard part.


So for now, I think you're best off finding out if rzrecovery supports your device variant, and if so, using it until there is a version of ClockworkMod for it.  I own ROM Manager Premium and have no complaints, and I really respect Koush for the work he does.