Hi Markpx and welcome to Forum!
Which screenmode resolution are you running AmiKit 8 on? Perhaps it's too high and that's why the mouse pointer is small? A resolution of 1024x768 or similar is enough.
Which AmigaOS have you used to install AmiKit? I just launched AmiKit 8 here with AmigaOS3.9 and it seems the pointer is as big as the Windows one, hmmm. Perhaps if you used older AmigaOS 3.1 there's smaller mouse pointer?
Perhaps try this: Open AmiKit:Prefs/Pointer program, press right-mouse button and from the menu select Project > Open, and go to Pointers folder and select any HiRes mouse preset, and then press Test or Use button. Or in Pointers/MorePointers/pointers folder there's definitely a bigger (and bit weird) pointer called "AmgaPointer".
Btw. AmiKit 8 is not a demo. It's a full product. Just old
Hope it helps?