Windows 95 Thai Version and applications which depend on that version (such as Word 98, Thai Version) can be used with the Lao-only fonts, but cannot be safely used with Lao Script for Windows since the keyboard manager and coding for Lao Script for Windows fonts conflict with the Thai codepage conventions. Lao fonts can be installed, and documents using Saysettha Lao or other Lao fonts can be safely viewed, but editing with the Thai versions may be unreliable.
The Thai additions to Lao Script for Windows provide a limited capability for entering and editing Thai text, and (in Version 6) also support the use of Thai fonts provided with Windows 95 and later.
The ThaiMaster application for using Thai language with international versions of Windows conflicts with the keyboard manager in Lao Script for Windows and cannot be used simultaneously, although it can of course be installed for use after closing the Lao Script for Windows keyboard manager application.
Is it possible to enter Lao using the Thai keyboard layout?
Lao Script for Windows was developed primarily for users within the Lao PDR, who are familiar with the Lao typewriter layout, and does not support the use of the Thai keyboard layout for entering Lao. The Thai layout, however, is used for entering or editing Thai text when the Thai-to-Lao translation option has been installed.