passing GET variables in exception to rewrite rule in web.config - iis

Question

I have a web.config file set up on an IIS box, which sends all web requests to a single index.php file, with two exceptions, which go to their intended destinations, as follows:
<?xml version="1.0" encoding="UTF-8"?>
<configuration>
<system.webServer>
<rewrite>
<rules>
<rule name="redirect all requests" stopProcessing="true">
<match url="^(.*)$" ignoreCase="true" />
<conditions logicalGrouping="MatchAll">
<add input="{REQUEST_FILENAME}" matchType="IsFile" negate="true" pattern="" ignoreCase="true" />
<add input="{REQUEST_URI}" negate="true" pattern="^/app/Library/editor/$" ignoreCase="true" />
<add input="{REQUEST_URI}" negate="true" pattern="^/app/Library/editor$" ignoreCase="true" />
<add input="{REQUEST_URI}" negate="true" pattern="^/its/$" ignoreCase="true" />
<add input="{REQUEST_URI}" negate="true" pattern="^/its$" ignoreCase="true" />
</conditions>
<action type="Rewrite" url="index.php" appendQueryString="true" />
</rule>
</rules>
</rewrite>
</system.webServer>
</configuration>
The exceptions work fine, in that http://servername/its, or http://servername/its/ serves up the correct page, but when there are parameters included in the request, eg, http://servernae/its/?value1=value2, it returns a page not found error.
I have a feeling that it is something obvious I have missed, but what do I need to add/change to get http://servernae/its/?value1=value2 to work as expected?
Regards