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I'm gathering that IonCube is a data obfuscation device.
The loader decrypts code that was previously encrypted by a vendor. While this is a good protection method from the vendor's point of view it also means you have to have complete faith that the script poses no security threat to your site. Personally I wouldn't use anything that cloaks itself in an encrypted form.
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I already have a WP site working, and I don't want the install to take the site down.
Note thread topic 
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Likely, everything will work as smoothly as it did before...
...I don't yet know if IonCube is working or not, even though the test said it did.
Your unbridled confidence is overwhelming 
It uses the official ionCube test files that are distributed with the loaders themselves. The test file actually reads an ionCube encrypted file, so if it says it was successful then you can be 100% (+50G) positive that ionCube is loading correctly.
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The debug script had one line with an x in it
Without the nx reference I couldn't be positive, but it's most likely an indication that you already had a cgi-bin folder. The script is a crop from a different project and about 4 or 5 of those lines would be relevant when using it in it's cutdown form to install PHP with ionCube on Sarge, Etch, or VPS.
I'll try put some time aside later to post some info regarding how it all works in the forum (link is in the zip) later and detail the debug output for those who might be interested.