dbo.Vocation contains a column that holds the last time one used transskill. There's no stored procedues targeting that database, your best bet is modifying that column everytime you use trans, which is a pain.
A simple hack would be changing this value everytime one uses transskill, allowing to use trans 1 time on every map with no cooldown. I did this trigger script, however I can't test it right now.
Run this as a query on MSSQL database (untested)
Code:
USE [heroes]
GO
/****** Object: Trigger [dbo].[noTransCD] Script Date: 10/21/2016 12:06:10 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TRIGGER [dbo].[noTransCD] ON [dbo].[Vocation]
FOR UPDATE
AS
declare @Cid int;
select @Cid=i.CID from inserted i;
UPDATE dbo.Vocation SET LastTransform = '2000-01-01' WHERE CID = @Cid;
GO