You may have to do this from the base developement mode and not Best Practice Development Mode.
Please try using Base developement mode.if it is already enabled, disable and save the form and enable it again.
I'm sorry that I didn't respond yesterday, but the advise given by AD is just plain wrong.
You followed the processes as you are supposed to, and according to my understanding of your setup, it should have worked. The best suggestion I can give you is to contact BMC and have them verify if it's a bug with your version/patch, and if it's fixed with a later patch/version, but following AD's advise is not advisable because anything done in base mode is at risk of getting overwritten by an upgrade, which you should avoid if you can.
I'm not in any way saying that the approach you suggested wouldn't work, I'm just stating that it's not a good idea and shouldn't be needed. BMC introduced the Overlay concept to allow for slick upgrades without losing any of your customizations, and if you do something in base, you aren't utilizing that new mechanism and risk losing your changes. Tarun didn't mention what version or patch they are on...their issue may be corrected in a later patch/version, but just staying on the version they are on and not figuring out when/how it's fixed I personally feel is a bad idea.