Since the toolkits (including IMAQ stuff) are built partly in LV, it HAS to recompile them for them to run. Since you say that a VI that's part of a toolkit has no block diagram, then no, you can't use it. You are not the first to complain about the problems in compatibility between different versions of LV. There are technical difficulties with this, and you will find opinions in both ways.
You've run into a unique situation because the VI was shipped without a block diagram. Anyway, it's possible that in all the legal mumbo-jumbo that came with IMAQ 6.0 you will find that you're only allowed to use it with LV 6.0 (I'm sure there are people here who know). I believe that the only practicle solution is upgrading (or, if it's legal, and if this is the only VI you're missing, have someone send you just that VI).
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