The conversion rules do fill the better part of half a chapter, and can't easily be reproduced in any detail. Three methods are used for the conversion of the characters and equipment statistics, and referees are encouraged to consider which method best supports the game system being entered.
The first method is to match attribute values, usually by using the game definitions of encumbrance to set the Multiverser strength against the game system strength, and extrapolating this to other scores. This method is usually sufficient, as most games have a physical strength score carefully defined in lifting and carrying definitions. The second method is to match probabilities. Multiverser's Appendix 3: Basic Dicing Curves contains information on the various methods used with dice, the probability curves these create, and the method for calculating them (along with a few simple programs in BASIC for calculating these by computer) so that the referee can determine what percent of characters would land at any particular value in a system, and place that against Multiverser's percentiles. The third method is to match concepts. Most games define "normal human" abilities, and many identify maximum human abilities, minimum human abilities, and super-human abilities in some detail. Since Multiverser gives similar concepts to its scale, a relational scale between systems can be established on that basis, most useful either if the game is less well suited to the other two systems or if the referee is doing the conversion "on the fly".
There are also rules controling how and when Multiverser rules supersede those of the game system, and when game system rules override Multiverser rules. Entering another game system without doing violence either to the game system or to the character is not simple in concept, and of necessity has some complex nuances; but the game has a lot of simple (and, once perceived, obvious) rules to make this smooth and quick.
Conversion of time frames between games is handled also, but as Multiverser uses a "real time" system--defining all actions in hours, minutes, or seconds--this is extremely straightforward. Damage conversions are based on comparable weapon types. I have as a test-player taken my character into White Wolf, and the conversion was actually quite fluid. As a referee, I have run Multiverser characters in AD&D, Star Frontiers, and Metamorphosis Alpha. Other referees have run players in several other games, including Champions, without complication.
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