[Other SmartWatches] Golem_:
I'll try to answer to all your question

- The processor seems to be "BBCHIP: MT6261_Dev_S0001". So is it MT6261D or MT6261DA or how do I find it out??

And also how do I find out the company name and model name?

if your flash is 3 or 4 MB then is 6261 for sure, if 8 MB it could be 6261 or 2502C, if 16 or 32MB then 6260 or 2502A

there is no such things like company or model name - it is only a company producing the PCB+processor and the OS version related and hundreds of anonyms building different watches around the pcb

- Is it okay to do like that? I mean, using any scatter config of other MT6261D devices? Does it vary for different variants/clones?

yes, scatter file is like a flash structure switch - it does not influence in any way your readback dump - roughly said, readback reads whole data from your flash

- Most of them had touch issues, a few had inverted screen and inverted colors. Any idea how to fix the latter problem? I can see that the dump is just a raw binary dump, I mean to ask is there any tricks to hexedit it and modify?

because we created here on XDA and (independently of us) 4PDA solid methods in order to replace the firmware starting with 6261, all the factories asked for their brand personalized firmware (matter of concurrency) - there is no way to fix this, I don't know anyone who can read/write assembly code-machine

- And, what is the difference between Internal Bootloader (INT_BOOTLOADER - 8KB) and External Bootloader (EXT_BOOTLOADER - 32KB). Or what are they?

I guess they are initialisers, one for primary structure and the other for external references - for instance FAT zone

- Also, what are the files 'FILE_01_mtk' (PRIMARY_MAUI - ROM) & 'FILE_02_mtk' (VIVA) and what do they contain? Are they like separate partitions of the smartwatch? Or just a raw dump split of everything (except BLs) into 2?

they are the OS, ROM is static direct readable zone, it contains all fast operations, VIVA is an archived bulk from where the system is picking the necessary routines unzipping them as static format in a small cache zone

- Is it possible to flash just my BL along with the ROM files of other firmwares? Will that work?

Yes

- It would be helpful if you can post the source code of the 'Readback Extractor mtk 2.4.exe' so that it will be useful for others in the future to extend it for different devices.

readback extractor (all versions) has about 150000 downloads only here on XDA - at this kind of exposure it wouldn't be very wise from my side - I'm an old school who knows how easy a virus could be written inside a small unofficial popular app - I wouldn't like my work to be used for instance as mining bitcoin trojan

- Can you please provide the download links of mtk_6261D_reader-writer.jar and dz09.jar. I can't seem to find it anywhere.

check the attachment - I'm trying to find the guy who wrote this java piece of software - it looks like after he made it public on 4PDA he disappeared in thin air

- Also, if you know Russian, can you please download all the tools listed here in the Download Section and upload it in a new thread in XDA

I don't speak russian but hey, nowadays the language is still a barrier? It wouldn't be a fair move to use them as a source but I will ask their smartwatch moderators to create here on XDA a full feature thread ( all my gratitude for dfgigger who made possible a rich communication between XDA and 4PDA)