Like at least one other Vim / gVim 7.4 for Windows user, I'm going 'round and 'round in circles trying to get gVim to properly display Unicode. In my case, I have a .py file that contains Thai characters. For example, เมษายน.
If in Windows 7 64-bit, I open the file in gVim 7.4, depending on which options I'm experimenting with, I get either rectangles or "line noise".
If in Windows, I open the file in Notepad++ or jEdit or the Eclipse PyDev editor, the Thai characters are correctly presented. Fast, simple.
If in Windows, I open the file in Geany 1.23.1 or Bluefish 2.2.5 for Windows, I get some nifty boxes, one per Thai character, all of which begin with x0E then a one-byte hex character code.
If in gVim 7.4 running under Mint Linux, I open the file the Thai characters are correctly displayed.
My first thought was that in my Windows gVim instance, I merely need to duplicate the fileencodings settings from my Linux gVim instance, ala fileencodings=ucs-bom,utf-8,default,latin1. I also duplicated the Linux instance's termencoding=utf-8.
All that accomplished was that the Thai characters were displayed as a random string of "line noise" rather than, say, one empty box per Thai character.
As confirmed by posts by several gVim 7.4 for Windows users, in gVim 7.4 the :version command lists multi_byte_ime/dyn but NOT multi_byte. See, inter alia:
Have Vim fully support UTF-8 on Windows
This differs from the gVim 7.4 instance running in Linux where :version DOES list multi_byte but does NOT include multi_byte_ime/dyn.
Evidently multi_byte_ime is about input method whereas multi_byte seems to be about supporting multi-byte characters(?) Whatever the significance of the two different ":version" outputs, I simply can't get gVim 7.4 for Windows to display the Thai characters whereas gVim 7.4 in Mint Linux does it straightaway.
At this point I'm trying to figure out a way forward. I've gone 'round and 'round and 'round reading different forums and experimenting with various options that purport to enable gVim 7.4 for Windows to display the Thai characters. So far I've gotten nowhere.