Kontakt should play your acid files. I don't know if they will keep the acidized info or just play it back as a wave file.
Kontakt can be got cheaply - esp. this time of the year. It should be on half price. I got a heavyocity library w/ player - you can pick up Player for free at NI. It won't play other official libraries except in demo mode. But for dropping acid files you can see how it works - tho there is a steep learning curve. I then picked up Kontakt for $200 or so - good investment if you want to mess w/ sampling and about as cheap as any other big library synth.
There is a free sampler - TXZ or something. There was another thread about it. It is supposed to be pretty good, esp. for the price.
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