That is a windows report. Mac does not use registry because all the program files are within the program itself (unless it has installed a Receipt file which is easily deleted via the library -> Receipts folder called Install LimeWire.pkg (afaik it's only used for installation permissions).) LW does have a preferences folder however.
Yes, a new account is like a different user on the computer so all settings are different.
The idea was to 'delete' the problematic incomplete file via the 'other' account.
Not open LW in there. But you'd need to Cancel the download & close LW before you try that. Then find the incomplete file & delete it. I had forgotten your LW download folder is probably in your user account (which other accounts will have no access to). I personally use a different hard disk drive to download files to. In your main account, open the system drive -> Users -> select your Username folder, hold down Command (apple) key & i key
⌘ i then in the information window, go to bottom, click the lock to unlock & make changes, enter password, then click the + sign, add your 'other' user account name to list (in example below I used Admin). Then select that users privilege & change to Read & Write. Then click the other drop down menu & choose Apply to enclosed items. Then go to your 'other' account & open the folders from there & find the incomplete folder, find that file & delete it.
Click attachment to see full view.