Tavultesoft Keyman was initially created as an input method for use with Lao Script for Windows. However, since version 5 of Lao Script for Windows, input mapping has been integrated as part of the application, to make it feasible to implement dictionary-based word-wrap, integrated with the Lao spell-checker provided through the Lao Add-In for Microsoft Word.
If you need to produce documents containing text in other languages for which KeyMan keyboards exist, you can temporarily exit LaoKey (the keyboard manager provided with Lao Script for Windows) by using the context (pop-up) menu from the Lao icon in the taskbar. But remember that Word will automatically restart LaoKey when it starts. If you want to prevent this, you can move the Lao Add-In (LSWin6xx.dot) out of the Word Startup folder to another location (such as the User Templates folder) and only load it when required.
Current versions of Lao Script for Windows automatically detect if KeyMan is loaded and provide the option of using it instead of LaoKey. Refer to the Lao Help Menu (or the Readme.txt release notes) for further details. However, you should be aware that older versions of KeyMan do not work with Windows NT, 2000 or XP.