Trying to write a macro that deletes all but the first and last N conditional formats.

Excel 2007 has a bug that generates tons of spurious copies of the (desired, user-generated conditional formatting as you copy-paste ranges. I can delete all at once easily enough, but then I have to recreate each desired conditional format. Or I can manually delete the spurious ones through the Excel toolbar interface, but I have to choose and confirm each single deletion, and these can number in the hundreds, thanks to this bug.

So, here's my code:

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1. You'd think that setting cond as type FormatCondition would make it a member of type FormatConditions, but then the line 
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produces a "Type mismatch" error. So, I changed it to Variant.

2. As type Variant, it produces an error on the line 
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"Application-defined or object-defined error".

3. So, I tried using a simple counter:
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Same "Application-defined or object-defined error".

OK, there's obviously some bugs in MS Excel's application model (unless I'm missing an obvious mistake or three). Anyone know a workaround?