Ok, after many (many) attempts and research, finally got the Dell HSPA 5530 WWAN Mini card working on a Dell Latitude laptop (in that case a 6420 XFR rugged) under Windows 7 x64Bits. The challenge is that you have to get the right combination of device drivers, and wireless manager version, as well force through the installation of the 5530 device, that check for a valid combination of laptop model / device and will reject the 5530 on this device.

Here is what you need :

• A Dell Latitude laptop with a WWAN mini card slot, and the SIM Card slot (usually behind the battery), with pre-cabled antennas in the chassis. Fit the card into the chassis, shoud appear in Windows as an unknown device. Make sure BIOS setting is not interferring with disabled WWAN option.
• The Windows 7 driver for the WWAN 5530 card, version A07, for Windows x64bits. You can find it here on Dell support web site Dell Wireless 5530 HSPA Mini-Card, v.Driver: v4.50.6.0 Co-installer: v1.0.12.1, A07. The name of the file is « DELL_WIRELESS-5530-HSPA-MINI_A07_R220899.exe ». This is a 10MBytes file.
• The Dell Wireless Manager software, that comes inside a 10Mbytes file you can find on Dell Support at Dell Wireless 5530 HSPA Mini-Card, v.5.2.1045.60, A02
• The Microsoft Orca MSI editor file, you can  find details and download link here
• The approach used by Remko to force through the installation of the driver on the laptop (3x deactivating Authentication checks in MSI) documented on his blog here. 

Here are the steps :

• Install the A02 applicatin 100Mbytes package first. This will get you the Wireless Manager on your Laptop. It won’t detect the device, because the WWAN card driver is not installed. That is OK.
• Install the A07 driver of the card, this will fail with an error message that this card is not valid for this laptop. Use Remko’s approach, to NOT terminate the installer, but before closing it copy paste from the temp folder the whole temporary decompressed install folder, and then paste this somewhere in a place you have write access to. Terminate the installer that rejected the install, then edit the MSI file as documented by Remko by removing in 3 different places the authentication check. Re-run then the MSI package from there, that should install 3 new devices on your unit, that is a HSPA network card, a HSPA Modem, and a SIM Card slot.
• Reboot, you are good to go. You shall now open the Wireless Manager application and see your card, turn the radio on, input your PIN code for the SIM and get connected. This will appear as a wired LAN connection to other programs when connected.

I tried other combination of Dell Control Point Connection Manager, or newer Wireless Manager, or not using Wireless Manager at all, or using different driver release, they all failed. The only one found working is A07 for the driver, and then A02 for the application call Wireless Manager.