I am aware the very early versions of LW 5 had limits of 10 on maximum downloads at one time (unless you still had LW preferences from LW version 4 & max downloads was set higher), but the later LW 5 versions do allow more. Mine is set to 20, I changed to 4, left preferences. I returned & changed it back to 20 with ease. I simply typed in the number. That was on a mac computer. On my Windows version, the arrow allows you to keep increasing, & can type in the number. Maximum downloads is 999. lol
Sounds to me like you are using an older version of LW 5? Present version is LW 5.5.14 ... you can find out via the Help menu -> About LW.

One thought is you delete your LW preferences after backing up the Downloads.dat file. Try deleting your LW Preferences folder whilst LW is closed; instructions here: Deleting LW's preferences folder.
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