I am very probably doing something wrong here, but cant figure out quite what.
VMMaker.ini
; VideoModeMaker - Options
; ------------------------
    
; 1. MAME
; -------
; Path for Mame executable, in case we want to extract xml information from it.
	MameExe = "..\mame.exe"
; Path for Mame ini folder, in case we want to create an ini file for each game.
; Important: existing ini files will be overwritten.
	IniPath = "\Emu\Mame\ini\"
; Mame options.
	ListFromXML = 1		; Processes Mame XML and get video mode list from it
	GenerateXML = 0		; Extracts XML from Mame (only needed once)
	GenerateInis = 0	; Creates an ini file for each Mame game, in the IniPath folder
	SDLMame = 0		; Use SDLMame specific options
; Monitor orientation
	MonitorHorizontal = 1	; 0 = Rotating monitor: horizontal and vertical games at their native resolution
				;     Suitable for users that physically rotate their CRTs
				; 1 = Horizontal monitor: horizontal games run at their native resolution and
				;     vertical games are rotated to fit in horizontal monitor	
	RotatingDesktop = 0	; Specifies if both desktop and monitor are rotated
; Aspect ratio for vertical games on horizontal monitor
; 	4:3 (keeps original aspect ratio)
; 	3:3 (stretches to square format)
; 	3:4 (stretches to full screen)
;	h:v (custom aspect ratio)
	VerticalAspect = "4:3"
; 2. MONITOR
; ----------
; Monitor Type. Valid types: D9800, D9400, D9200, EGA, VGA, MULTI, H9110, PAL, NTSC, GENERIC, CUSTOM
	MonitorType = "CUSTOM"
; Monitor CUSTOM. These values will be used if MonitorType = "CUSTOM"
;
; monitor_specs_0-6 = "HfreqMin-HfreqMax, VfreqMin,VfreqMax, HFrontPorch, HSyncPulse, HBackPorch, VfrontPorch, VSyncPulse, VBackPorch, HSyncPol, VSyncPol, ActiveLinesLimit, VirtualLinesLimit"
;
; 	* HfreqMin-HfreqMax: Minimum and maximum horizontal frequency, in Hz. Defines the range of horizontal frequencies the monitor is capable to sync.
; 		The higher the horizontal frequency, the higher the vertical resolution available for the same vertical refresh.
; 		The higher the horizontal frequency, the higher the vertical refresh available for the same vertical resolution.
; 		The higher the horizontal frequency, the lower the horizontal amplitude of active video (narrower picture).
;
;	* VFreqMin-VfreqMax: Minimum and maximum vertical frequency, in Hz, Defines the range of vertical frequencies the monitor is capable to sync.
;
;	* HFrontPorch, HSyncPulse, HBackPorch: Horizontal timing and geometry, values in µs
;
;	* VfrontPorch, VSyncPulse, VBackPorch: Vertical timing and geometry, values in ms
;
;	* HSyncPol,VSyncPol: polarities, not in use! defaults to negative.
;
;	* ActiveLinesLimit: Vertical resolutions until ActiveLinesLimit value included, are generated as progressive, regardless the possibility
;                           of obtaining the required vertical refresh value.
;
;	* VirtualLinesLimit: Vertical resolutions above ActiveLinesLimit and below VirtualLinesLimit are virtualized, that is, an interlaced resolution
;                            bigger that the native one is generated, with the right refresh, and "hardware stretch" is applied.
;                            Vertical resolutions above VirtulaLinesLimit are generated as interlaced, without any stretching.
	monitor_specs_0 = "30000-40000, 47.00-90.00, 0.600, 2.500, 2.800, 0.032, 0.096, 0.448, 0, 0, 640, 768"
; Tolerance for horizontal frequency, in kHz, enables extending the range defined by [ HfreqMin, HfreqMax ]
; The resulting allowed frequency range will be [ HfreqMin - HfreqTolerance, HfreqMax + HfreqTolerance ]
	HfreqTolerance = 0.010
; 3. MODELINE GENERATOR
; ---------------------
; Total number of modelines to generate. Here are the recommended values for each driver version:
; CRT_Emudriver, based on Catalyst 6.5 XP32:	160 modes (accepts up to 200, but above 160 HyperSpin will refuse to load)
; CRT_Emudriver, based on Catalyst 6.5 XP64:	120 modes
; CRT_Emudriver, based on Catalyst 9.3 XP32/64:	120 modes (accepts some more but above 120 you can get some blue screens)
; Regular Catalyst:				 60 modes (won't accept any more)
	TotalModes = 100
; Method for mode table generation. If Mame xml is processed, that will create a lot of different video modes, so the mode table
; will be optimized keeping the most relevant ones, and dropping the rest, to keep below the TotalModes value.
	ModeTableMethod = 1	; 0 = Static table: modelines are generated keeping their original vertical refresh. This
				;     method is intended to be used in combination with ini files for each game. 
				; 1 = Dynamic table: a table of dummy modes is created using xres and yres values while ignoring
				;     vfreq. This method is intended to be used in combination with Switchres or Groovymame. No ini
				;     files are required using this method (you should disable the GenerateInis option).
; Minimum resolution values (these will be used instead of lower values)
	XresMin = 208
	YresMin = 192
; Minimum dotclock value allowed by the video card, in MHz (i.e. DotClockMin = 7.010)
	DotClockMin = 18.500
; Number of iterations used by the mode generator [0,5]. The higher the number of iterations, the bigger the accuracy of the vertical
; refreshed obtained, normally at the cost of increasing the horizontal frequency strictly required.
	Iterations = 2
; Specifies if the refresh label is multiplied by 10 before rounding (experimental).
	VFreqLabelx10 = 0
; 4. DRIVER
; ---------
; Path for the driver folder
	DriverPath = ".\Driver\"
; If UpdateRegistry is enabled, UpdateDriver will only work if the driver version found in DriverPath matches the one installed
; in the system.
	UpdateRegistry = 1	; Specifies if the video card registry section will be updated with the new video modes
				; (will only work in combination with CRT_EMUDriver).
		
	UpdateDriver = 0	; Specifies if the driver files in DriverPath will be updated with the new video modes, for
				; future installations.
	AnyCatalyst = 0		; Allows modelines to be installed for any Catalyst version. This option is experimental and
				; known to produce some problems.
Only32BPPModes = 1
And my ReslList.txt
## Commodore ##
640 x 480 @ 50.000000 c64
1280 x1024 @ 50.000000 amiga
As far as I can see neither resolution at the requested refresh has been added after I run VMMaker.exe and reset.
Any help appreciated, Thanks!