Created this fighter design and it is having the armor rounding issue when clicking "Update Armour".
You can add additional 5tons of components after clicking "Update Armour" but after revisiting the designer the size will return to be too big
Pebble class Geological Survey Craft 495 tons 13 Crew 117,9 BP TCS 10 TH 13 EM 0
1314 km/s Armour 1-5 Shields 0-0 HTK 2 Sensors 0/0/0/1 DCR 0 PPV 0
Maint Life 0 Years MSP 0 AFR 98% IFR 1,4% 1YR 52 5YR 776 Max Repair 100 MSP
Follower Control Rating 1
Intended Deployment Time: 4 months Morale Check Required
Fighter NT Engine EP13,50 (1) Power 13,5 Fuel Use 173,21% Signature 13,50 Explosion 10%
Fuel Capacity 20 000 Litres Range 4,2 billion km (37 days at full power)
Geological Survey Sensors (1) 1 Survey Points Per Hour
This design is classed as a Fighter for production, combat and planetary interaction
Also noticed that Fighter Engineering Space gives 14MSP but on some setups this gets bumped up to 15MSP when clicking the "Update Armour"
An example:
Pebble class Geological Survey Craft 495 tons 14 Crew 118,6 BP TCS 10 TH 13 EM 0
1315 km/s Armour 1-5 Shields 0-0 HTK 2 Sensors 0/0/0/1 DCR 0 PPV 0
Maint Life 1,38 Years MSP 15 AFR 20% IFR 0,3% 1YR 9 5YR 128 Max Repair 100 MSP
Follower Control Rating 1
Intended Deployment Time: 3 months Morale Check Required
Fighter NT Engine EP13,50 (1) Power 13,5 Fuel Use 173,21% Signature 13,50 Explosion 10%
Fuel Capacity 15 000 Litres Range 3,2 billion km (27 days at full power)
Geological Survey Sensors (1) 1 Survey Points Per Hour
This design is classed as a Fighter for production, combat and planetary interaction