Global bug?

[Verjigorm]

In order to know for sure we'd have to know if there were 5-6 active globals on the F6 screen. If there were 5 active globals, his would have become the 6th and then yours would've failed to overwrite it. If a third player cast another spell, it may have subsequently overpowered it. This spell would appear as active on the list--not yours or the one that overpowered yours.
Example:

Here's an F6 Screen:

1. (Player A) Arcane Nexus
2. (Player B) Forge of Ancients
3. (Player C) A Well of Misery
4. (Player A) Purgatory
5. (Player C) Gale Gate
6. --OPEN--

Assuming the most probable scenario we will have something like:

Player A casts Stellar Focus
Player C casts Utterdark

The computer selects the random order for Ritual magic and it ends up being C, A.

C's Utterdark goes off at 999 Death gems, filling the 6th slot.

A's Stellar focus with a puny 60 gems goes off contesting (by random draw) the 6th slot occupied by said Utterdark spell. Unless A is inconceivably lucky, his spell will be bLasted out of existance and he shall receive a message stating that it was overpowered by the existing enchantment.