See feedback below.
From Chandan: "Hi, I know you are pretty busy, however, I am stuck at the part where I have the boat but do not have the ship to venture out in the deep sea. Please can you make a guide for people like me like you have for Episodes 1-3? It may be a short one just as a simple walkthrough. I see in the steam forums that many like me are struggling. Thank you in advance."
Hello Chandan, thank you for getting in touch. Unfortunately, as the future of the E2 project is unclear, I don't feel terribly motivated to work on another walkthrough. Moreover, as you observed, I'm quite involved with other things at the moment. But I'm always happy to provide assistance on a case-by-case basis. The situation you described is very broad, however, and constitutes a large portion of the game.
Generally, after getting Hamati's sailboat, you need to sail east to Behgar Jungle, where you'll recruit Raya. After getting Raya, you proceed deeper into the jungle to Maia's Garden, where you'll fight Lupe. After defeating Lupe, you sail south to Mt. Golgotha and Castle Dragonheart. I wrote a partial walkthrough of Castle Dragonheart for someone on the Aldorlea forum. After you leave there, you return to Fiyara and proceed north into the desert, and that leads into Episode 5. You get the ship in Glymac at the end of Episode 5, and that's the end of the current content.