Problems with flash and signal

Hi.
I have a HTC ON M8 that bought a few days ago. 4.4.2 android had K.K., so I decided fastboot flash by. He had signal problems since it was unstable and could not connect to 3g or 4g. Only 2g. I descargueé install the USB drivers for htc, I placed the fastboot folder in c: \ fastboot, but it has given me some problems. I can perfectly restart in bootoader mode, verify mid, cid, model, but did not leave me any zip flash. I can not unlock the bootloader with Unlock_code because it gives me error. Displays a warning that could not be loaded.
Because of this, I had to update by UCP. Download 0P6BIMG_M8_UL_M60_SENSE70_MR_HTC_Europe_6.12.401.4 _Radio_1.29.214500021.12G_20.72.4196t.01_release_4 64360_signed and I put it on my SD card. The process did not produce errors, but incender my M8, threw a warning in red letters, "device tree is not totally matched." After setting my M8, I noticed that the signal was much more unstable. In almost all times no signal, and when it does, it is going slowly.
I'm really desperate. I do not know what to do, friends. I am from Chile, South America, and the M8 should work well with 4g (2600) and 3g networks.
These are the RUU I installed, but have not given me a solution to my problem:
- 0P6BIMG_M8_UL_M60_SENSE70_MR_HTC_Europe_6.12.401.4 _Radio_1.29.214500021.12G_20.72.4196t.01_release_4 64360_signed
- 0P6BIMG_M8_UL_L50_SENSE60_MR_HTC_Europe_4.16.401.1 0_Radio_1.25.214500021.06G_20.68.4196t.01_F_releas e_417809_signed
- 0P6BIMG_M8_UL_K444_SENSE60_MR_HTC_Europe_3.28.401. 9_R_Radio_1.22.21331147A1.29G_20.67.4196.01_releas e_402839_signed

I'll leave information about my HTC ONE M8:

(bootloader) version: 0.5
(bootloader) version-bootloader: 3.19.0.0000
(bootloader) version-baseband: 1.25.214500021.06G
(bootloader) version-cpld: None
(bootloader) version-microp: None
(bootloader) version-main: 4.16.401.10
(bootloader) version-misc: XF SHIP S-OFF
(bootloader) serialno: HT43TWM04554
(bootloader) imei: 358714053025548
(bootloader) imei2: Not Support
(bootloader) meid: 00000000000000
(bootloader) product: m8_ul
(bootloader) platform: hTCBmsm8974
(bootloader) modelid: 0P6B10000
(bootloader) cidnum: HTC__001
(bootloader) battery-status: good
(bootloader) battery-voltage: 0mV
(bootloader) partition-layout: Generic
(bootloader) security: off
(bootloader) build-mode: SHIP
(bootloader) boot-mode: FASTBOOT
(bootloader) commitno-bootloader: 3aa067db
(bootloader) hbootpreupdate: 11
(bootloader) gencheckpt: 0

I hope you can help me, please.
Regards.