Did Devorah have prophecy for the future?
Radak: No, her prophecy was only for her time. 1
Rashi (5:31) says that the end of her Shirah "v'Ohavav k'Tzeis ha'Shemesh bi'Gevuraso" is a prophecy for the future (after Mashi'ach).
What is the meaning of "Eshes Lapidos"?
Rashi: She 1 used to make wicks for [the Menorah in] the Mikdash.
Tana d'Vei Eliyahu Rabah (10): She was Barak's wife; he is also called Lapidos. Radak - Lapidos (flames) is like Barak (lightning).
Malbim: Her actions were with zeal and excitement, like flames. She merited prophecy, unlike the previous saviors. Her merit was one of four reasons why Yisrael merited to be saved. 2
Can a woman be a judge?
Tosfos (Nidah 50a) #1: Yes! Only regarding men, 'anyone Kosher to judge is Kosher to testify.'
Tosfos (Nidah 50a) #2: It was a Hora'as Sha'ah to let her judge; normally it is forbidden.
Tosfos (Nidah 50a) #3: She did not judge; she taught the laws to them.
Tosfos (Gitin 88b): (If both parties agree, they can accept a judge Pasul for judging.) People accepted her due to Shechinah.
What tense is "Shoftah"?
Radak #1: It is past tense, from a verb form like Merubah. 1
Radak #2: It is present tense. (Normally, it should say Shofetes, but) we find like this - "Esh Ochlah Kash" (Yo'el 2:5).
I.e. the Vov (Cholem, even though it is written without a Vov) is part of a four-letter root. This is Radak's opinion; some grammarians reject this. (Heard from R. Yakov Blinde.)