There really shouldn't be an error coming up during the installation.
Can you please try it again, choose the software/script you want to install, hit install and so on, write the proper information it asks you for (the username...password...) and if you get an error,
Can you please take a screen shot of it, and post it here, as it's unusual for this to happen. I want to see everything it says regarding the error...
Maybe you are using too much sql databases I beleive free hosting members have a limit to how much databases they are using. Please check the number of databases you are currently using.
Thank you,
John Klyne.