*Some tricks done in demos (e.g. overscan) are still slightly broken in MESS.
*Loading extension ROMs is also not supported.
==JavaScript port==
MESS has also recently been ported to JavaScript using the C/C++-to-JS transcompiler Emscripten; this port is called [http://jsmess.textfiles.com/ JSMESS]. A fork that has the necessary Makefiles to build the CPC 6128 version is here: [https://github.com/mdoege/jsmess]
Note that cpc6128.zip also needs to contain the ROM files from cpc464.zip because unlike regular MESS, JSMESS only loads a single ROM ZIP file per machine.
Currently, sound only works in Firefox and not in Chrome/Chromium.
==Links==