Forde's heroic save denied Huddersfield's David Unsworth spot-kick after Tony Craig was found guilty of a clumsy trip on Michael Collins after the second-half substitute had darted into the Lions box.
Forde guessed the right way and the full back's left-footed shot rebounded of the Irishman's chest and as the Lions fans held their breath, he managed to race to his feet to gather.
Liam Dickinson opened the scoring for the visitors with a stunning overhead kick on 18 minutes, having reacted quickest to Nathan Clarke's long throw, leaving Forde with absolutely no chance.
But Tresor Kandol took the sides into the break level when he rose highest in the Huddersfield area to powerfully head home Chris Hackett's pin-point cross
The game, poised on a knife-edge, was eventually decided by Lewis Grabban's 62nd minute winner, as he calmly slotted home under the body of out-rushing keeper Matt Glennon after an incisive Neil Harris through ball.
On 82 minutes, Huddersfield skipper Chris Lucketti's saving covering tackle denied Kandol a sure second after the Congolese international raced on to Hackett's through ball.
Harris thought he had extended the Lions lead himself two minutes later when his delicate chip rebounded off both posts, after the veteran striker raced into the clear after a neat reverse pass from Grabban.
But as the 7,500 home fans began to enjoy their first win of the season, the late drama stopped everybody in their tracks when referee Keith Hill controversially pointed to the spot.
Afterwards, Town boss Stan Ternent insisted he will not quit despite finding his side rock-bottom of League One with four games gone.