Hi,
If you are using the "normal" SAP "PC Editor" in Smartform Builder, you need to manually enter the RTF Font Information for the Font Family you just installed in order to see fonts in editor. If you have not yet done so, check 130658 - SAPscript: New fonts in the PC Editor on how to get the right RTF stuff, maintain those in SE73 and let me know if there is still problem after that.
cheers
Jānis