I really like the litebag which you developed. However, I play on a private server of World of Warcraft. I'm highly expectant that you would develop a litebag which can work on 3.3.5 version. I'm willing to provide financial support. Thank you.

This release for Cataclysm Classic might work on a Wrath private server. 4.4.1-2-cata

You could also try the last Wrath version; 3.4.3-2-wrath.

There are no major changes in the bag API between Vanilla and Dragonflight. The only major change was Blizzard backporting the settings menus to Cata in 4.1.1, so you could also try the previous version before that:
4.4.0-4-cata.

The github releases page has most of the recent old versions for download. One might work.

If none of them work you can paste me the errors (after setting /console scripterrors 1) and I'll see if I can suggest any fixes. I don't have any way to develop for a private server, nor any spare time really.

I am very sorry for making such an excessive request to you. Thank you very much for your reply. I have tried many versions, but none of them works properly. However, the 4.4.1.2-cata version reports relatively fewer errors. The Lua errors collected by me using !BaudErrorFrame addons are as follows.
`[string "LiteBagBankMoneyFrame:OnLoad"]:2: attempt to call global 'MoneyFrame_SetMaxDisplayWidth' (a nil value)
Count: 1

Call Stack:
[C]: in function `MoneyFrame_SetMaxDisplayWidth'
[string ":OnLoad"]:2: in function <[string ":OnLoad"]:1>

Interface\AddOns\LiteBag\LiteBagBank.lua:20: attempt to index field 'CloseButton' (a nil value)
Count: 1

Call Stack:
[C]: ?
Interface\AddOns\LiteBag\LiteBagBank.lua:20: in function <Interface\AddOns\LiteBag\LiteBagBank.lua:16>

[string "LiteBagInventoryMoneyFrame:OnLoad"]:2: attempt to call global 'MoneyFrame_SetMaxDisplayWidth' (a nil value)
Count: 1

Call Stack:
[C]: in function `MoneyFrame_SetMaxDisplayWidth'
[string ":OnLoad"]:2: in function <[string ":OnLoad"]:1>

Interface\AddOns\LiteBag\ReplaceBlizzard.lua:19: attempt to concatenate global 'CONFIRM_CONTINUE' (a nil value)
Count: 1

Call Stack:
[C]: ?
Interface\AddOns\LiteBag\ReplaceBlizzard.lua:19: in main chunk

Interface\AddOns\LiteBag\Plugin_BindsOn\BindsOn.lua:31: attempt to index global 'BATTLENET_FONT_COLOR' (a nil value)
Count: 1

Call Stack:
[C]: ?
Interface\AddOns\LiteBag\Plugin_BindsOn\BindsOn.lua:31: in main chunk

Interface\AddOns\LiteBag\UI\UIOptions.lua:20: attempt to index field 'Text' (a nil value)
Count: 1

Call Stack:
[C]: ?
Interface\AddOns\LiteBag\UI\UIOptions.lua:20: in function <Interface\AddOns\LiteBag\UI\UIOptions.lua:19>

Interface\AddOns\LiteBag\UI\UIOptions.lua:39: attempt to index field 'Text' (a nil value)
Count: 1

Call Stack:
[C]: ?
Interface\AddOns\LiteBag\UI\UIOptions.lua:39: in function <Interface\AddOns\LiteBag\UI\UIOptions.lua:38>

Interface\AddOns\LiteBag\UI\UIOptions.lua:58: attempt to index field 'Text' (a nil value)
Count: 1

Call Stack:
[C]: ?
Interface\AddOns\LiteBag\UI\UIOptions.lua:58: in function <Interface\AddOns\LiteBag\UI\UIOptions.lua:57>`

Hi. I looked at this quite a but but unfortunately the game at that stage did not have a number of the UI templates that LiteBag relies on. Also the addon XML API does not support the "mixin" mechanism, so the templates can't be copied back from a later version.

Sorry, looks like it's not possible without writing an entirely new addon.

I used to use Bagnon back in the day, perhaps that still works.