I have received an e.mail from a friend detailing each of the types, so am posting this for anyone interested and to close this thread.

Bottom right is the XT-001 prototype built by the Self-Reliance Development Wing of the Philippine Air Force in 1975. It was a 2/3-seat primary trainer with a 260-hp Lycoming O-540-E4A5 flat-6. Yes it looks suspiciously like an SF260, which of course the PAF had in service at the time! Janes suggested that the prototype was in fact converted from an SF260!

Bottom left is the Philippine Air Transport & Training Services Inc (PATS School of Aeronautics)/National Science Development Board Project 7307En PATS Bamboo Aircraft. Project 7307En was entitled ‘Research on local fabric, local woods and local aluminium for aircraft use’. The aircraft was claimed to have flown 26 hours of successful tests. It was a 2-seat trainer with an 85-hp engine, main undercarriage and instruments from a Piper Cub. Fuselage and wings of native bamboo, covered with ramie tetoron fabric. Prop carved from Manggachapui hardwood.

The glider top right is labelled XG-002 or XG-00Z, which must mean it is the XG-001 2-seat glider built by Philippine Air Transport & Training Services Inc (PATS School of Aeronautics)/National Science Development Board at the same time as the Bamboo Aircraft.

Top left is the M600 Parasol, which was registered to Gonzales-Palpal-Latoc in Manila. I don’t have any other reference to it being an indigenous design, it looks suspiciously like a Pietenpol or a Corben baby Ace!