Hello,
in order to use larger fonts on your target, it might be necessary to increase the size of the glyph cache that is used by the Graphics Engine. The size of the glyph cache is defined by the macros EW_MAX_GLYPH_SURFACE_WIDTH and EW_MAX_GLYPH_SURFACE_HEIGHT. You will find them within the makefile.
Alternatively, if you want to show only a couple of large characters (e.g. to show large digits), you can use alpha8 bitmaps. Please have a look to this article, which explains the solution.
Concerning the performance difference: The graphical performance of an UI application depends on the used MCU and the used graphics operations. If you are using huge warp operations (e.g. rotation or scaling) which are not hardware accelerated, it will take a lot of CPU power on the embedded system. The resulting graphics performance on a high-end Windows PC will be always different than on a MCU with limited or no hardware acceleration. There is no difference between Free Edition or Professional Edition in this aspect.
Best regards,
Manfred.