Still happening with Patch 8.2.5:

Date: 2019-10-15 11:42:28
ID: 8
Error occured in: Global
Count: 1
Message: ..\AddOns\tdBattlePetScript_Rematch\Addon.lua line 40:
Usage: GetPetInfoByID(petGUID)
Debug:
(tail call): ?
[C]: GetPetInfoByPetID()
tdBattlePetScript_Rematch\Addon.lua:40: GetPetTip()
tdBattlePetScript_Rematch\Addon.lua:59: tipFormatting()
tdBattlePetScript\UI\UI.lua:31:
tdBattlePetScript\UI\UI.lua:17
(tail call): ?
tdBattlePetScript\UI\PetBattle.lua:180:
tdBattlePetScript\UI\PetBattle.lua:178
(tail call): ?
[C]: ?
[string "safecall Dispatcher[3]"]:9:
[string "safecall Dispatcher[3]"]:5
(tail call): ?
...PetScript\Libs\tdGUI\Libs\LibClass-2.0\Class-2.0.lua:156: Fire()
...Ons\tdBattlePetScript\Libs\tdGUI\Widget\ViewItem.lua:28: FireHandler()
...Ons\tdBattlePetScript\Libs\tdGUI\Widget\ViewItem.lua:59:
...Ons\tdBattlePetScript\Libs\tdGUI\Widget\ViewItem.lua:57
Locals:
None

When you open the menu and mousever the things in the script selector:

Date: 2018-12-20 21:08:42
ID: 1
Error occured in: Global
Count: 1
Message: ..\AddOns\tdBattlePetScript_Rematch\Addon.lua line 40:
Usage: GetPetInfoByID(petGUID)
Debug:
[C]: GetPetInfoByPetID()
tdBattlePetScript_Rematch\Addon.lua:40: GetPetTip()
tdBattlePetScript_Rematch\Addon.lua:59: tipFormatting()
tdBattlePetScript\UI\UI.lua:31:
tdBattlePetScript\UI\UI.lua:17
(tail call): ?
tdBattlePetScript\UI\PetBattle.lua:180:
tdBattlePetScript\UI\PetBattle.lua:178
(tail call): ?
[C]: ?
[string "safecall Dispatcher[3]"]:9:
[string "safecall Dispatcher[3]"]:5
(tail call): ?
...PetScript\Libs\tdGUI\Libs\LibClass-2.0\Class-2.0.lua:156: Fire()
...Ons\tdBattlePetScript\Libs\tdGUI\Widget\ViewItem.lua:28: FireHandler()
...Ons\tdBattlePetScript\Libs\tdGUI\Widget\ViewItem.lua:59:
...Ons\tdBattlePetScript\Libs\tdGUI\Widget\ViewItem.lua:57
Locals:
None

After 8.1: 

Date: 2018-12-11 17:49:41
ID: 1
Error occured in: Global
Count: 1
Message: ..\AddOns\tdBattlePetScript_Rematch\v4.lua line 78:
Usage: SecureHook([object], method, [handler]): Attempting to hook a non existing target

After updating Rematch to 4.8.10-exp-06, I get the following LUA error on login:

Message: ..\AddOns\tdBattlePetScript_Rematch\v3.lua line 22:
attempt to index field 'menu' (a nil value)
Debug:
tdBattlePetScript_Rematch\v3.lua:22:
tdBattlePetScript_Rematch\v3.lua:21
[C]: ?
Ace3\AceAddon-3.0\AceAddon-3.0.lua:70:
Ace3\AceAddon-3.0\AceAddon-3.0.lua:65
Ace3\AceAddon-3.0\AceAddon-3.0.lua:527:
Ace3\AceAddon-3.0\AceAddon-3.0.lua:520
(tail call): ?
...Ons\tdBattlePetScript\Core\Manager\PluginManager.lua:161: LoadPlugins()
...Ons\tdBattlePetScript\Core\Manager\PluginManager.lua:33:
...Ons\tdBattlePetScript\Core\Manager\PluginManager.lua:32

1x tdBattlePetScript_Rematch\Addon.lua:46: Usage: GetPetInfoByID(petGUID)
[C]: in function `GetPetInfoByPetID'
tdBattlePetScript_Rematch\Addon.lua:46: in function `GetPetTip'
tdBattlePetScript_Rematch\Addon.lua:65: in function `tipFormatting'
tdBattlePetScript\UI\UI.lua:28: in function `OpenScriptTooltip'
tdBattlePetScript\UI\MainPanel.lua:147: in function <tdBattlePetScript\UI\MainPanel.lua:146>

Locals:
(*temporary) = "random:8"

I have no idea what I'm supposed to be doing here. I read through the script creation, had only the import option, so used that, but then there's no save option, not even if I try it on one of the sample scripts. Is there some beginning/ending command I'm missing?

x1 AceLocale-3.0-6: tdBattlePetScript_Rematch: Missing entry for 'Team:'
Stack: tdBattlePetScript_Rematch\Addon.lua:52: in function 'tipFormatting'
tdBattlePetScript\UI\UI.lua:28: in function 'OpenScriptTooltip'
tdBattlePetScript\UI\MainPanel.lua:147: in function <tdBattlePetScript\UI\MainPanel.lua:146>
Time: 2018/01/24 23:36:57 Index: 1/1
Locals:

x1 AceLocale-3.0-6: tdBattlePetScript_Rematch: Missing entry for 'Team:'
Stack: tdBattlePetScript_Rematch\Addon.lua:52: in function 'tipFormatting'
tdBattlePetScript\UI\UI.lua:28: in function 'OpenScriptTooltip'
tdBattlePetScript\UI\MainPanel.lua:147: in function <tdBattlePetScript\UI\MainPanel.lua:146>
Time: 2018/01/24 23:36:57 Index: 1/1
Locals:

I have a question:

If I export the tabs data from Rematch, does it also export the tdBattlePetScript Rematch scripts?

for the addon author - Interface bug =(

that no add for translation line

 and new option Rematch

06/18/2017 version 4.7.0
- Added two new slot types: Ignored and Random.