I'm not sure if this will help, since I don't use FSharp myself, but there is a ViEmu command that may help you in this case. You can select a ViEmu visual range as you usually do and transform it into a Visual Studio selection through the command gS. I guess it will be accepted then by FSI.
There is also the option of turning on the 'Use VS selection for visual mode' in ViEmu settings, of course.
I hope it helps...

Regards,

Isaac

I was wondering if anyone could help me with this problem:

I don't want to have to select text with my mouse to send it to FSharp Interactive (by alt-enter or right-clicking on top of the selected block).

It takes time, and I can simply press V and have the entire block selected by ViEmu within a couple of keystrokes.

My problem is that after selecting the text, FSI will not accept the code block from ViEmu.

Is there anything I can do to fix this?