There is a number of restrictions on formulas which are placed by ESMA, and as such, we cannot remove them.
As you probably know, it is mandatory to state to the authorities how you calculate your figures, so we translate your formulas into XBRL calculations - but there are restrictions within XBRL on how you calculate items (you can read more about it here.)
To keep accounting consistency, iXBRL does not allow certain calculations from debit to credit and vice versa. In short, you can't just use add and subtract as you want to between debit and credit elements.
As an example, the “Cash flow from operations” subtotal would normally be a debit and “Profit (loss)” would be a credit.
It is not allowed to do a positive sum from credit to debit – but to allow this quite common calculation in CF where “Cash flow from operations” includes “Profit (loss)”, “Cash flow from operations” has been given a “null”/blank debit/credit attribute.
The “Calculation relationship has illegal weight” problem arises if you create subtotal extensions in CF like “Cash flow from operations before adjustments to net finance expenses” as iXBRL does not allow you to extend the taxonomy without adding a debit/credit (balance) attribute.
How to Fix the Issue
Currently there is no solution available aside from disregarding the validation errors or remove the calculation.